diff --git a/libs/spandsp/src/ademco_contactid.c b/libs/spandsp/src/ademco_contactid.c
index 975525adb8..d26fab4a2c 100644
--- a/libs/spandsp/src/ademco_contactid.c
+++ b/libs/spandsp/src/ademco_contactid.c
@@ -755,7 +755,7 @@ SPAN_DECLARE(ademco_contactid_receiver_state_t *) ademco_contactid_receiver_init
 {
     if (s == NULL)
     {
-        if ((s = (ademco_contactid_receiver_state_t *) span_alloc(sizeof (*s))) == NULL)
+        if ((s = (ademco_contactid_receiver_state_t *) span_alloc(sizeof(*s))) == NULL)
             return NULL;
     }
     memset(s, 0, sizeof(*s));
@@ -1090,7 +1090,7 @@ SPAN_DECLARE(ademco_contactid_sender_state_t *) ademco_contactid_sender_init(ade
 {
     if (s == NULL)
     {
-        if ((s = (ademco_contactid_sender_state_t *) span_alloc(sizeof (*s))) == NULL)
+        if ((s = (ademco_contactid_sender_state_t *) span_alloc(sizeof(*s))) == NULL)
             return NULL;
     }
     memset(s, 0, sizeof(*s));
diff --git a/libs/spandsp/src/dtmf.c b/libs/spandsp/src/dtmf.c
index 48a8836337..1ff725ff22 100644
--- a/libs/spandsp/src/dtmf.c
+++ b/libs/spandsp/src/dtmf.c
@@ -417,7 +417,7 @@ SPAN_DECLARE(dtmf_rx_state_t *) dtmf_rx_init(dtmf_rx_state_t *s,
 
     if (s == NULL)
     {
-        if ((s = (dtmf_rx_state_t *) span_alloc(sizeof (*s))) == NULL)
+        if ((s = (dtmf_rx_state_t *) span_alloc(sizeof(*s))) == NULL)
             return NULL;
     }
     memset(s, 0, sizeof(*s));
@@ -578,7 +578,7 @@ SPAN_DECLARE(dtmf_tx_state_t *) dtmf_tx_init(dtmf_tx_state_t *s,
 {
     if (s == NULL)
     {
-        if ((s = (dtmf_tx_state_t *) span_alloc(sizeof (*s))) == NULL)
+        if ((s = (dtmf_tx_state_t *) span_alloc(sizeof(*s))) == NULL)
             return NULL;
     }
     memset(s, 0, sizeof(*s));
diff --git a/libs/spandsp/src/gsm0610_encode.c b/libs/spandsp/src/gsm0610_encode.c
index c810fa2c69..7621f22adc 100644
--- a/libs/spandsp/src/gsm0610_encode.c
+++ b/libs/spandsp/src/gsm0610_encode.c
@@ -116,12 +116,12 @@ SPAN_DECLARE(gsm0610_state_t *) gsm0610_init(gsm0610_state_t *s, int packing)
 {
     if (s == NULL)
     {
-        if ((s = (gsm0610_state_t *) span_alloc(sizeof (*s))) == NULL)
+        if ((s = (gsm0610_state_t *) span_alloc(sizeof(*s))) == NULL)
             return NULL;
         /*endif*/
     }
     /*endif*/
-    memset((char *) s, '\0', sizeof (gsm0610_state_t));
+    memset((char *) s, '\0', sizeof(gsm0610_state_t));
     s->nrp = 40;
     s->packing = packing;
     return s;
diff --git a/libs/spandsp/src/msvc/inttypes.h b/libs/spandsp/src/msvc/inttypes.h
index 032ec3c36c..8d680e27db 100644
--- a/libs/spandsp/src/msvc/inttypes.h
+++ b/libs/spandsp/src/msvc/inttypes.h
@@ -33,7 +33,7 @@ typedef __int16		        int16_t;
 typedef __int32		        int32_t;
 typedef __int64		        int64_t;
 
-#if !defined(INFINITY)
+#if !defined(INFINITY)  &&  _MSC_VER < 1800
 #define INFINITY 0x7FFFFFFF
 #endif
 
diff --git a/libs/spandsp/src/spandsp/at_interpreter.h b/libs/spandsp/src/spandsp/at_interpreter.h
index 1b6e1f7771..67ca4c0b77 100644
--- a/libs/spandsp/src/spandsp/at_interpreter.h
+++ b/libs/spandsp/src/spandsp/at_interpreter.h
@@ -173,7 +173,6 @@ SPAN_DECLARE(void) at_set_class1_handler(at_state_t *s, at_class1_handler_t hand
     \return A pointer to the logging context */
 SPAN_DECLARE(logging_state_t *) at_get_logging_state(at_state_t *s);
 
-
 SPAN_DECLARE(void) at_set_modem_control_handler(at_state_t *s,
                                                 at_modem_control_handler_t modem_control_handler,
                                                 void *modem_control_user_data);
diff --git a/libs/spandsp/src/spandsp/bit_operations.h b/libs/spandsp/src/spandsp/bit_operations.h
index c7f4093ab3..7b5b5aface 100644
--- a/libs/spandsp/src/spandsp/bit_operations.h
+++ b/libs/spandsp/src/spandsp/bit_operations.h
@@ -53,13 +53,13 @@ static __inline__ int top_bit(uint32_t bits)
              : [res] "=&r" (res)
              : [bits] "rm" (bits));
     return res;
-#elif defined(__GNUC__x)  &&  (defined(__ARM_ARCH_6__)  ||  defined(__ARM_ARCH_7A__))
+#elif defined(__GNUC__)  &&  (defined(__ARM_ARCH_6__)  ||  defined(__ARM_ARCH_7A__))
     int res;
 
     __asm__("clz %[res], %[bits]"
             : [res] "=r" (res)
             : [bits] "r" (bits));
-    return res;
+    return 31 - res;
 #elif defined(__ppc__)  ||   defined(__powerpc__)
     int res;
 
diff --git a/libs/spandsp/src/spandsp/fir.h b/libs/spandsp/src/spandsp/fir.h
index 554a36c372..85be5d2a6f 100644
--- a/libs/spandsp/src/spandsp/fir.h
+++ b/libs/spandsp/src/spandsp/fir.h
@@ -38,8 +38,6 @@
 #include "mmx.h"
 #endif
 
-#include "alloc.h"
-
 /*!
     16 bit integer FIR descriptor. This defines the working state for a single
     instance of an FIR filter using 16 bit integer coefficients.
diff --git a/libs/spandsp/src/spandsp/plc.h b/libs/spandsp/src/spandsp/plc.h
index 6d5c301073..2c2f7ca3fa 100644
--- a/libs/spandsp/src/spandsp/plc.h
+++ b/libs/spandsp/src/spandsp/plc.h
@@ -111,7 +111,6 @@ That's it!
 */
 typedef struct plc_state_s plc_state_t;
 
-
 #if defined(__cplusplus)
 extern "C"
 {
diff --git a/libs/spandsp/src/spandsp/private/time_scale.h b/libs/spandsp/src/spandsp/private/time_scale.h
index 775046161d..1b55a00874 100644
--- a/libs/spandsp/src/spandsp/private/time_scale.h
+++ b/libs/spandsp/src/spandsp/private/time_scale.h
@@ -34,15 +34,27 @@
 /*! Audio time scaling descriptor. */
 struct time_scale_state_s
 {
+    /*! \brief The sample rate of both the incoming and outgoing signal */
     int sample_rate;
+    /*! \brief The minimum pitch we will search for, in samples per cycle */
     int min_pitch;
+    /*! \brief The maximum pitch we will search for, in samples per cycle */
     int max_pitch;
-    int buf_len;
+    /*! \brief The playout speed, as the fraction output time/input time.
+         (i.e. >1.0 == slow down, 1.0 == no speed change, <1.0 == speed up) */
     float playout_rate;
+    /*! \brief */
     double rcomp;
+    /*! \brief The fractional sample adjustment, to allow for non-integer values of lcp. */
     double rate_nudge;
-    int fill;
+    /*! \brief */
     int lcp;
+    /*! \brief The active length of buf at the current sample rate. */
+    int buf_len;
+    /*! \brief The number of samples in buf */
+    int fill;
+    /*! \brief Buffer for residual samples kept over from one call of time_scale() to
+        the next. */
     int16_t buf[TIME_SCALE_BUF_LEN];
 };
 
diff --git a/libs/spandsp/src/spandsp/t30_api.h b/libs/spandsp/src/spandsp/t30_api.h
index 90cefc4f58..e6b47fb877 100644
--- a/libs/spandsp/src/spandsp/t30_api.h
+++ b/libs/spandsp/src/spandsp/t30_api.h
@@ -28,11 +28,33 @@
 #if !defined(_SPANDSP_T30_API_H_)
 #define _SPANDSP_T30_API_H_
 
+enum
+{
+    T33_NONE = 0,
+    T33_SST = 1,
+    T33_EXT = 2
+};
+
 #if defined(__cplusplus)
 extern "C"
 {
 #endif
 
+/*! Get the specified field from a T.33 formatted string.
+    \brief Get the specified field from a T.33 formatted string.
+    \param field The extracted field.
+    \param t33 The T.33 formatted string.
+    \param field_no The field number to extract. The first field is 0.
+    \return The extracted field type. -1 indicates a over length or badly formatted field. */
+SPAN_DECLARE(int) t33_sub_address_extract_field(uint8_t field[21], const uint8_t t33[], int field_no);
+
+/*! Append the specified field to a T.33 formatted string.
+    \brief Append the specified field to a T.33 formatted string.
+    \param t33 The T.33 formatted string.
+    \param field The field to be adppended.
+    \param type The type of the field to be appended. */
+SPAN_DECLARE(void) t33_sub_address_add_field(uint8_t t33[], const uint8_t field[], int type);
+
 /*! Set the transmitted NSF frame to be associated with a T.30 context.
     \brief Set the transmitted NSF frame to be associated with a T.30 context.
     \param s The T.30 context.
diff --git a/libs/spandsp/src/spandsp/time_scale.h b/libs/spandsp/src/spandsp/time_scale.h
index 666cca7a78..35e8e00fe7 100644
--- a/libs/spandsp/src/spandsp/time_scale.h
+++ b/libs/spandsp/src/spandsp/time_scale.h
@@ -62,25 +62,6 @@ extern "C"
 {
 #endif
 
-/*! Initialise a time scale context. This must be called before the first
-    use of the context, to initialise its contents.
-    \brief Initialise a time scale context.
-    \param s The time scale context.
-    \param sample_rate The sample rate of the signal.
-    \param playout_rate The ratio between the output speed and the input speed.
-    \return A pointer to the context, or NULL if there was a problem. */
-SPAN_DECLARE(time_scale_state_t *) time_scale_init(time_scale_state_t *s, int sample_rate, float playout_rate);
-
-/*! \brief Release a time scale context.
-    \param s The time scale context.
-    \return 0 for OK, else -1. */
-SPAN_DECLARE(int) time_scale_release(time_scale_state_t *s);
-
-/*! \brief Free a time scale context.
-    \param s The time scale context.
-    \return 0 for OK, else -1. */
-SPAN_DECLARE(int) time_scale_free(time_scale_state_t *s);
-
 /*! Change the time scale rate.
     \brief Change the time scale rate.
     \param s The time scale context.
@@ -108,6 +89,27 @@ SPAN_DECLARE(int) time_scale_max_output_len(time_scale_state_t *s, int input_len
 */
 SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[], int len);
 
+SPAN_DECLARE(int) time_scale_flush(time_scale_state_t *s, int16_t out[]);
+
+/*! Initialise a time scale context. This must be called before the first
+    use of the context, to initialise its contents.
+    \brief Initialise a time scale context.
+    \param s The time scale context.
+    \param sample_rate The sample rate of the signal.
+    \param playout_rate The ratio between the output speed and the input speed.
+    \return A pointer to the context, or NULL if there was a problem. */
+SPAN_DECLARE(time_scale_state_t *) time_scale_init(time_scale_state_t *s, int sample_rate, float playout_rate);
+
+/*! \brief Release a time scale context.
+    \param s The time scale context.
+    \return 0 for OK, else -1. */
+SPAN_DECLARE(int) time_scale_release(time_scale_state_t *s);
+
+/*! \brief Free a time scale context.
+    \param s The time scale context.
+    \return 0 for OK, else -1. */
+SPAN_DECLARE(int) time_scale_free(time_scale_state_t *s);
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/libs/spandsp/src/t30.c b/libs/spandsp/src/t30.c
index bd24898b3e..1a51f2fc2f 100644
--- a/libs/spandsp/src/t30.c
+++ b/libs/spandsp/src/t30.c
@@ -436,6 +436,7 @@ static void decode_20digit_msg(t30_state_t *s, char *msg, const uint8_t *pkt, in
 static void decode_url_msg(t30_state_t *s, char *msg, const uint8_t *pkt, int len);
 static int decode_nsf_nss_nsc(t30_state_t *s, uint8_t *msg[], const uint8_t *pkt, int len);
 static void set_min_scan_time(t30_state_t *s);
+static int send_cfr_sequence(t30_state_t *s, int start);
 static int build_dcs(t30_state_t *s);
 static void timer_t2_start(t30_state_t *s);
 static void timer_t2a_start(t30_state_t *s);
@@ -1309,7 +1310,6 @@ int t30_build_dis_or_dtc(t30_state_t *s)
     /* No Document transfer mode (DTM) */
     /* No Electronic data interchange (EDI) */
     /* No Basic transfer mode (BTM) */
-
     /* No mixed mode (polling) */
     /* No character mode */
     /* No mixed mode (T.4/Annex E) */
@@ -5492,9 +5492,9 @@ static void timer_t2_expired(t30_state_t *s)
             /* We didn't receive a response to our T30_MCF after T30_EOM, so we must be OK
                to proceed to phase B, and pretty much act like its the beginning of a call. */
             span_log(&s->logging, SPAN_LOG_FLOW, "Returning to phase B after %s\n", t30_frametype(s->next_rx_step));
+            s->dis_received = false;
             set_phase(s, T30_PHASE_B_TX);
             timer_t2_start(s);
-            s->dis_received = false;
             send_dis_or_dtc_sequence(s, true);
             return;
         }
@@ -5548,6 +5548,13 @@ static void timer_t2a_expired(t30_state_t *s)
 {
     span_log(&s->logging, SPAN_LOG_FLOW, "T2A expired in phase %s, state %s. An HDLC frame lasted too long.\n", phase_names[s->phase], state_names[s->state]);
     t30_set_status(s, T30_ERR_HDLC_CARRIER);
+    /* T.30 says we should retry at this point, but we can't. We would need to
+       wait for the far end to go quiet before sending. Experience says you only
+       get here when the far end is buggy, and it will not go quiet unless you
+       hang up. If we were to retry, how long should we wait for the line to go
+       quiet? T.30 doesn't specify things like that. The only effective strategy,
+       when trying to deal with problems found in logs from real world systems,
+       is to abandon the call. */
     terminate_call(s);
 }
 /*- End of function --------------------------------------------------------*/
@@ -5571,7 +5578,8 @@ static void timer_t4_expired(t30_state_t *s)
 {
     /* There was no response (or only a corrupt response) to a command,
        within the T4 timeout period. */
-    span_log(&s->logging, SPAN_LOG_FLOW, "T4 expired in phase %s, state %s\n", phase_names[s->phase], state_names[s->state]);
+    if (s->timer_t2_t4_is == TIMER_IS_T4)
+        span_log(&s->logging, SPAN_LOG_FLOW, "T4 expired in phase %s, state %s\n", phase_names[s->phase], state_names[s->state]);
     /* Of course, things might just be a little late, especially if there are T.38
        links in the path. There is no point in simply timing out, and resending,
        if we are currently receiving something from the far end - its a half-duplex
@@ -6143,9 +6151,9 @@ SPAN_DECLARE(void) t30_front_end_status(void *user_data, int status)
         {
         case T30_STATE_ANSWERING:
             span_log(&s->logging, SPAN_LOG_FLOW, "Starting answer mode\n");
+            s->dis_received = false;
             set_phase(s, T30_PHASE_B_TX);
             timer_t2_start(s);
-            s->dis_received = false;
             send_dis_or_dtc_sequence(s, true);
             break;
         case T30_STATE_R:
diff --git a/libs/spandsp/src/t30_api.c b/libs/spandsp/src/t30_api.c
index 5bf164b998..724dcf9735 100644
--- a/libs/spandsp/src/t30_api.c
+++ b/libs/spandsp/src/t30_api.c
@@ -95,6 +95,65 @@
 
 #include "t30_local.h"
 
+SPAN_DECLARE(int) t33_sub_address_extract_field(uint8_t num[21], const uint8_t t33[], int field_no)
+{
+    int i;
+    int j;
+    int k;
+    int ch;
+    int type;
+
+    num[0] = '\0';
+    k = 0;
+    for (i = 0;  t33[i];  )
+    {
+        if (k++ == field_no)
+        {
+            ch = t33[i++];
+            j = 0;
+            if (ch != '#')
+            {
+                num[j++] = ch;
+                type = T33_EXT;
+            }
+            else
+            {
+                type = T33_SST;
+            }
+            while (t33[i])
+            {
+                ch = t33[i++];
+                if (ch == '#')
+                    break;
+                num[j++] = ch;
+                if (j >= 20)
+                    return -1;
+            }
+            num[j] = '\0';
+            return type;
+        }
+        /* Skip this field */
+        i++;
+        while (t33[i])
+        {
+            if (t33[i++] == '#')
+                break;
+        }
+    }
+    return T33_NONE;
+}
+/*- End of function --------------------------------------------------------*/
+
+SPAN_DECLARE(void) t33_sub_address_add_field(uint8_t t33[], const uint8_t field[], int type)
+{
+    if (t33[0] != '\0')
+        strcat((char *) t33, "#");
+    if (type == T33_SST)
+        strcat((char *) t33, "#");
+    strcat((char *) t33, (const char *) field);
+}
+/*- End of function --------------------------------------------------------*/
+
 SPAN_DECLARE(int) t30_set_tx_ident(t30_state_t *s, const char *id)
 {
     if (id == NULL)
diff --git a/libs/spandsp/src/t31.c b/libs/spandsp/src/t31.c
index 943063e8a2..e63eb229e8 100644
--- a/libs/spandsp/src/t31.c
+++ b/libs/spandsp/src/t31.c
@@ -2994,7 +2994,7 @@ SPAN_DECLARE(t31_state_t *) t31_init(t31_state_t *s,
     alloced = false;
     if (s == NULL)
     {
-        if ((s = (t31_state_t *) span_alloc(sizeof (*s))) == NULL)
+        if ((s = (t31_state_t *) span_alloc(sizeof(*s))) == NULL)
             return NULL;
         /*endif*/
         alloced = true;
diff --git a/libs/spandsp/src/t38_gateway.c b/libs/spandsp/src/t38_gateway.c
index 88b17352c4..4467a615ad 100644
--- a/libs/spandsp/src/t38_gateway.c
+++ b/libs/spandsp/src/t38_gateway.c
@@ -662,8 +662,8 @@ static void monitor_control_messages(t38_gateway_state_t *s,
                 /*endif*/
             }
             /*endfor*/
-            /* If we are processing a message from the modem side, the contents determine the fast receive modem.
-               we are to use. If it comes from the T.38 side the contents do not. */
+            /* If we are processing a message from the modem side, the contents determine the fast
+               receive modem we are to use. If it comes from the T.38 side the contents do not. */
             s->core.fast_bit_rate = modem_codes[i].bit_rate;
             if (from_modem)
                 s->core.fast_rx_modem = modem_codes[i].modem_type;
@@ -700,8 +700,9 @@ static void monitor_control_messages(t38_gateway_state_t *s,
                 /*endif*/
             }
             /*endfor*/
-            /* If we are processing a message from the modem side, the contents determine the fast receive modem.
-               we are to use. If it comes from the T.38 side the contents do not. */
+            /* If we are processing a DCS message from the modem side, the contents determine the fast
+               receive modem we are to use. If it comes from the T.38 side the contents do not. For a
+               DTC message this is reversed. */
             s->core.fast_bit_rate = modem_codes[i].bit_rate;
             if ((buf[2] == T30_DTC  &&  !from_modem)  ||  (buf[2] != T30_DTC  &&  from_modem))
                 s->core.fast_rx_modem = modem_codes[i].modem_type;
diff --git a/libs/spandsp/src/time_scale.c b/libs/spandsp/src/time_scale.c
index 5337e4ad0c..ea1f95c35c 100644
--- a/libs/spandsp/src/time_scale.c
+++ b/libs/spandsp/src/time_scale.c
@@ -78,12 +78,15 @@ static __inline__ int amdf_pitch(int min_pitch, int max_pitch, int16_t amp[], in
         acc = 0;
         for (j = 0;  j < len;  j++)
             acc += abs(amp[i + j] - amp[j]);
+        /*endfor*/
         if (acc < min_acc)
         {
             min_acc = acc;
             pitch = i;
         }
+        /*endif*/
     }
+    /*endfor*/
     return pitch;
 }
 /*- End of function --------------------------------------------------------*/
@@ -102,6 +105,7 @@ static __inline__ void overlap_add(int16_t amp1[], int16_t amp2[], int len)
         amp2[i] = (int16_t) ((float) amp1[i]*(1.0f - weight) + (float) amp2[i]*weight);
         weight += step;
     }
+    /*endfor*/
 }
 /*- End of function --------------------------------------------------------*/
 
@@ -130,52 +134,6 @@ SPAN_DECLARE(int) time_scale_rate(time_scale_state_t *s, float playout_rate)
 }
 /*- End of function --------------------------------------------------------*/
 
-SPAN_DECLARE(time_scale_state_t *) time_scale_init(time_scale_state_t *s, int sample_rate, float playout_rate)
-{
-    bool alloced;
-
-    if (sample_rate > TIME_SCALE_MAX_SAMPLE_RATE)
-        return NULL;
-    alloced = false;
-    if (s == NULL)
-    {
-        if ((s = (time_scale_state_t *) span_alloc(sizeof (*s))) == NULL)
-            return NULL;
-        /*endif*/
-        alloced = true;
-    }
-    /*endif*/
-    s->sample_rate = sample_rate;
-    s->min_pitch = sample_rate/TIME_SCALE_MIN_PITCH;
-    s->max_pitch = sample_rate/TIME_SCALE_MAX_PITCH;
-    s->buf_len = 2*sample_rate/TIME_SCALE_MIN_PITCH;
-    if (time_scale_rate(s, playout_rate))
-    {
-        if (alloced)
-            span_free(s);
-        return NULL;
-    }
-    /*endif*/
-    s->rate_nudge = 0.0f;
-    s->fill = 0;
-    s->lcp = 0;
-    return s;
-}
-/*- End of function --------------------------------------------------------*/
-
-SPAN_DECLARE(int) time_scale_release(time_scale_state_t *s)
-{
-    return 0;
-}
-/*- End of function --------------------------------------------------------*/
-
-SPAN_DECLARE(int) time_scale_free(time_scale_state_t *s)
-{
-    span_free(s);
-    return 0;
-}
-/*- End of function --------------------------------------------------------*/
-
 SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[], int len)
 {
     double lcpf;
@@ -191,10 +149,12 @@ SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[],
     if (s->fill + len < s->buf_len)
     {
         /* Cannot continue without more samples */
+        /* Save the residual signal for next time. */
         vec_copyi16(&s->buf[s->fill], in, len);
         s->fill += len;
         return out_len;
     }
+    /*endif*/
     k = s->buf_len - s->fill;
     vec_copyi16(&s->buf[s->fill], in, k);
     in_len += k;
@@ -208,15 +168,18 @@ SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[],
             if (len - in_len < s->buf_len)
             {
                 /* Cannot continue without more samples */
+                /* Save the residual signal for next time. */
                 vec_copyi16(s->buf, &in[in_len], len - in_len);
                 s->fill = len - in_len;
                 s->lcp -= s->buf_len;
                 return out_len;
             }
+            /*endif*/
             vec_copyi16(s->buf, &in[in_len], s->buf_len);
             in_len += s->buf_len;
             s->lcp -= s->buf_len;
         }
+        /*endwhile*/
         if (s->lcp > 0)
         {
             vec_copyi16(&out[out_len], s->buf, s->lcp);
@@ -225,15 +188,18 @@ SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[],
             if (len - in_len < s->lcp)
             {
                 /* Cannot continue without more samples */
+                /* Save the residual signal for next time. */
                 vec_copyi16(&s->buf[s->buf_len - s->lcp], &in[in_len], len - in_len);
                 s->fill = s->buf_len - s->lcp + len - in_len;
                 s->lcp = 0;
                 return out_len;
             }
+            /*endif*/
             vec_copyi16(&s->buf[s->buf_len - s->lcp], &in[in_len], s->lcp);
             in_len += s->lcp;
             s->lcp = 0;
         }
+        /*endif*/
         if (s->playout_rate == 1.0f)
         {
             s->lcp = 0x7FFFFFFF;
@@ -256,6 +222,7 @@ SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[],
                 s->lcp++;
                 s->rate_nudge += 1.0f;
             }
+            /*endif*/
             if (s->playout_rate < 1.0f)
             {
                 /* Speed up - drop a chunk of data */
@@ -264,10 +231,12 @@ SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[],
                 if (len - in_len < pitch)
                 {
                     /* Cannot continue without more samples */
+                    /* Save the residual signal for next time. */
                     vec_copyi16(&s->buf[s->buf_len - pitch], &in[in_len], len - in_len);
                     s->fill += (len - in_len - pitch);
                     return out_len;
                 }
+                /*endif*/
                 vec_copyi16(&s->buf[s->buf_len - pitch], &in[in_len], pitch);
                 in_len += pitch;
             }
@@ -278,15 +247,88 @@ SPAN_DECLARE(int) time_scale(time_scale_state_t *s, int16_t out[], int16_t in[],
                 out_len += pitch;
                 overlap_add(&s->buf[pitch], s->buf, pitch);
             }
+            /*endif*/
         }
+        /*endif*/
     }
+    /*endwhile*/
     return out_len;
 }
 /*- End of function --------------------------------------------------------*/
 
+SPAN_DECLARE(int) time_scale_flush(time_scale_state_t *s, int16_t out[])
+{
+    int len;
+    int pad;
+
+    if (s->playout_rate < 1.0f)
+        return 0;
+    /*endif*/
+    vec_copyi16(out, s->buf, s->fill);
+    len = s->fill;
+    if (s->playout_rate > 1.0f)
+    {
+        pad = s->fill*(s->playout_rate - 1.0f);
+        vec_zeroi16(&out[len], pad);
+        len += pad;
+    }
+    /*endif*/
+    s->fill = 0;
+    return len;
+}
+/*- End of function --------------------------------------------------------*/
+
 SPAN_DECLARE(int) time_scale_max_output_len(time_scale_state_t *s, int input_len)
 {
     return (int) (input_len*s->playout_rate + s->min_pitch + 1);
 }
 /*- End of function --------------------------------------------------------*/
+
+SPAN_DECLARE(time_scale_state_t *) time_scale_init(time_scale_state_t *s, int sample_rate, float playout_rate)
+{
+    bool alloced;
+
+    if (sample_rate > TIME_SCALE_MAX_SAMPLE_RATE)
+        return NULL;
+    /*endif*/
+    alloced = false;
+    if (s == NULL)
+    {
+        if ((s = (time_scale_state_t *) span_alloc(sizeof(*s))) == NULL)
+            return NULL;
+        /*endif*/
+        alloced = true;
+    }
+    /*endif*/
+    s->sample_rate = sample_rate;
+    s->min_pitch = sample_rate/TIME_SCALE_MIN_PITCH;
+    s->max_pitch = sample_rate/TIME_SCALE_MAX_PITCH;
+    s->buf_len = 2*sample_rate/TIME_SCALE_MIN_PITCH;
+    if (time_scale_rate(s, playout_rate))
+    {
+        if (alloced)
+            span_free(s);
+        /*endif*/
+        return NULL;
+    }
+    /*endif*/
+    s->rate_nudge = 0.0f;
+    s->fill = 0;
+    s->lcp = 0;
+    return s;
+}
+/*- End of function --------------------------------------------------------*/
+
+SPAN_DECLARE(int) time_scale_release(time_scale_state_t *s)
+{
+    return 0;
+}
+/*- End of function --------------------------------------------------------*/
+
+SPAN_DECLARE(int) time_scale_free(time_scale_state_t *s)
+{
+    span_free(s);
+    return 0;
+}
+/*- End of function --------------------------------------------------------*/
 /*- End of file ------------------------------------------------------------*/
diff --git a/libs/spandsp/src/v22bis_rx.c b/libs/spandsp/src/v22bis_rx.c
index 42c3e93c2a..102b9a2eb7 100644
--- a/libs/spandsp/src/v22bis_rx.c
+++ b/libs/spandsp/src/v22bis_rx.c
@@ -579,7 +579,7 @@ static __inline__ void process_half_baud(v22bis_state_t *s, const complexf_t *sa
             s->rx.gardner_step = 32;
         break;
     case V22BIS_RX_TRAINING_STAGE_UNSCRAMBLED_ONES:
-        /* Calling modem only */
+        /* Calling modem only. */
         /* The calling modem should initially receive unscrambled ones at 1200bps */
         target = &v22bis_constellation[nearest];
         track_carrier(s, &z, target);
@@ -621,7 +621,7 @@ static __inline__ void process_half_baud(v22bis_state_t *s, const complexf_t *sa
         }
         break;
     case V22BIS_RX_TRAINING_STAGE_UNSCRAMBLED_ONES_SUSTAINING:
-        /* Calling modem only */
+        /* Calling modem only. */
         /* Wait for the end of the unscrambled ones at 1200bps. */
         target = &v22bis_constellation[nearest];
         track_carrier(s, &z, target);
@@ -682,7 +682,7 @@ static __inline__ void process_half_baud(v22bis_state_t *s, const complexf_t *sa
                     /* The transmit side needs to sustain the scrambled ones for a timed period. */
                     s->tx.training_count = 0;
                     s->tx.training = V22BIS_TX_TRAINING_STAGE_TIMED_S11;
-                    /* Normal reception starts immediately */
+                    /* Normal reception starts immediately. */
                     s->rx.training = V22BIS_RX_TRAINING_STAGE_NORMAL_OPERATION;
 #if defined(SPANDSP_USE_FIXED_POINT)
                     s->rx.carrier_track_i = 8;