diff --git a/libs/freetdm/src/ftdm_io.c b/libs/freetdm/src/ftdm_io.c
index 1750d6d7d9..7fb5afdb59 100644
--- a/libs/freetdm/src/ftdm_io.c
+++ b/libs/freetdm/src/ftdm_io.c
@@ -2488,9 +2488,18 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_set_sig_status(ftdm_channel_t *ftdmchan,
 {
 	ftdm_assert_return(ftdmchan != NULL, FTDM_FAIL, "Null channel\n");
 	ftdm_assert_return(ftdmchan->span != NULL, FTDM_FAIL, "Null span\n");
-	
+
+	if (sigstatus == FTDM_SIG_STATE_DOWN) {
+		ftdm_log_chan_msg(ftdmchan, FTDM_LOG_WARNING, "The user is not allowed to set the signaling status to DOWN, valid states are UP or SUSPENDED\n");
+		return FTDM_FAIL;
+	}
+
 	if (ftdmchan->span->set_channel_sig_status) {
-		return ftdmchan->span->set_channel_sig_status(ftdmchan, sigstatus);
+		ftdm_status_t res;
+		ftdm_channel_lock(ftdmchan);
+		res = ftdmchan->span->set_channel_sig_status(ftdmchan, sigstatus);
+		ftdm_channel_unlock(ftdmchan);
+		return res;
 	} else {
 		ftdm_log(FTDM_LOG_ERROR, "set_channel_sig_status method not implemented!\n");
 		return FTDM_FAIL;
@@ -2504,7 +2513,11 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_get_sig_status(ftdm_channel_t *ftdmchan,
 	ftdm_assert_return(sigstatus != NULL, FTDM_FAIL, "Null sig status parameter\n");
 	
 	if (ftdmchan->span->get_channel_sig_status) {
-		return ftdmchan->span->get_channel_sig_status(ftdmchan, sigstatus);
+		ftdm_status_t res;
+		ftdm_channel_lock(ftdmchan);
+		res = ftdmchan->span->get_channel_sig_status(ftdmchan, sigstatus);
+		ftdm_channel_unlock(ftdmchan);
+		return res;
 	} else {
 		/* don't log error here, it can be called just to test if its supported */
 		return FTDM_NOTIMPL;
@@ -2515,6 +2528,11 @@ FT_DECLARE(ftdm_status_t) ftdm_span_set_sig_status(ftdm_span_t *span, ftdm_signa
 {
 	ftdm_assert_return(span != NULL, FTDM_FAIL, "Null span\n");
 	
+	if (sigstatus == FTDM_SIG_STATE_DOWN) {
+		ftdm_log(FTDM_LOG_WARNING, "The user is not allowed to set the signaling status to DOWN, valid states are UP or SUSPENDED\n");
+		return FTDM_FAIL;
+	}
+	
 	if (span->set_span_sig_status) {
 		return span->set_span_sig_status(span, sigstatus);
 	} else {
diff --git a/libs/freetdm/src/ftmod/ftmod_r2/ftmod_r2.c b/libs/freetdm/src/ftmod/ftmod_r2/ftmod_r2.c
index 5377250588..ccf7fdf89a 100644
--- a/libs/freetdm/src/ftmod/ftmod_r2/ftmod_r2.c
+++ b/libs/freetdm/src/ftmod/ftmod_r2/ftmod_r2.c
@@ -486,9 +486,6 @@ static FIO_CHANNEL_SET_SIG_STATUS_FUNCTION(ftdm_r2_set_channel_sig_status)
 				ftdm_r2_set_chan_sig_status(ftdmchan, status);
 			}
 			break;
-		case FTDM_SIG_STATE_DOWN:
-			ftdm_log_chan_msg(ftdmchan, FTDM_LOG_WARNING, "The user is not allowed to set signaling status to DOWN\n");
-			return FTDM_FAIL;
 		default:
 			ftdm_log_chan(ftdmchan, FTDM_LOG_WARNING, "Cannot set signaling status to unknown value '%d'\n", status);
 			return FTDM_FAIL;
@@ -508,10 +505,13 @@ static FIO_SPAN_GET_SIG_STATUS_FUNCTION(ftdm_r2_get_span_sig_status)
 	*status = FTDM_SIG_STATE_SUSPENDED;
 	for (citer = chaniter; citer; citer = ftdm_iterator_next(citer)) {
 		ftdm_channel_t *fchan = ftdm_iterator_current(citer);
+		ftdm_channel_lock(fchan);
 		if (ftdm_test_flag(fchan, FTDM_CHANNEL_SIG_UP)) {
 			*status = FTDM_SIG_STATE_UP;
+			ftdm_channel_unlock(fchan);
 			break;
 		}
+		ftdm_channel_unlock(fchan);
 	}
 	ftdm_iterator_free(chaniter);
 	return FTDM_SUCCESS;
@@ -522,11 +522,6 @@ static FIO_SPAN_SET_SIG_STATUS_FUNCTION(ftdm_r2_set_span_sig_status)
 	ftdm_iterator_t *chaniter = NULL;
 	ftdm_iterator_t *citer = NULL;
 
-	if (status == FTDM_SIG_STATE_DOWN) {
-		ftdm_log(FTDM_LOG_WARNING, "The user is not allowed to set the span signaling status to DOWN\n");
-		return FTDM_FAIL;
-	}
-
 	chaniter = ftdm_span_get_chan_iterator(span, NULL);
 	if (!chaniter) {
 		ftdm_log(FTDM_LOG_CRIT, "Failed to allocate channel iterator for span %s!\n", span->name);
@@ -537,9 +532,11 @@ static FIO_SPAN_SET_SIG_STATUS_FUNCTION(ftdm_r2_set_span_sig_status)
 		ftdm_channel_t *fchan = ftdm_iterator_current(citer);
 		/* we set channel's state through ftdm_r2_set_channel_sig_status(), since it already takes
 		 * care of notifying the user when appropriate */
+		ftdm_channel_lock(fchan);
 		if ((ftdm_r2_set_channel_sig_status(fchan, status)) != FTDM_SUCCESS) {
 			ftdm_log_chan(fchan, FTDM_LOG_ERROR, "Failed to set signaling status to %s\n", ftdm_signaling_status2str(status));
 		}
+		ftdm_channel_unlock(fchan);
 	}
 	ftdm_iterator_free(chaniter);
 	return FTDM_SUCCESS;