diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 384e843033..051bb2bc4d 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -28806,7 +28806,8 @@ static int check_rtp_timeout(struct sip_pvt *dialog, time_t t)
 					ast_channel_name(dialog->owner), (long) (t - dialog->lastrtprx));
 				send_session_timeout(dialog->owner, "RTPTimeout");
 
-				/* Issue a softhangup */
+				/* Issue a softhangup - cause 44 (as used by Cisco for RTP timeouts) */
+				ast_channel_hangupcause_set(dialog->owner, AST_CAUSE_REQUESTED_CHAN_UNAVAIL);
 				ast_softhangup_nolock(dialog->owner, AST_SOFTHANGUP_DEV);
 				ast_channel_unlock(dialog->owner);
 				/* forget the timeouts for this call, since a hangup