Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 417704)
+++ channels/chan_sip.c	(working copy)
@@ -7462,8 +7462,11 @@
 						ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
 					}
 				}
-				p->lastrtptx = time(NULL);
-				res = ast_rtp_instance_write(p->rtp, frame);
+				if (p->invitestate > INV_EARLY_MEDIA || (p->invitestate == INV_EARLY_MEDIA &&
+									 ast_test_flag(&p->flags[0], SIP_PROGRESS_SENT))) {
+					p->lastrtptx = time(NULL);
+					res = ast_rtp_instance_write(p->rtp, frame);
+				}
 			}
 			sip_pvt_unlock(p);
 		}
@@ -7480,8 +7483,11 @@
 					transmit_provisional_response(p, "183 Session Progress", &p->initreq, TRUE);
 					ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
 				}
-				p->lastrtptx = time(NULL);
-				res = ast_rtp_instance_write(p->vrtp, frame);
+				if (p->invitestate > INV_EARLY_MEDIA || (p->invitestate == INV_EARLY_MEDIA &&
+									 ast_test_flag(&p->flags[0], SIP_PROGRESS_SENT))) {
+					p->lastrtptx = time(NULL);
+					res = ast_rtp_instance_write(p->vrtp, frame);
+				}
 			}
 			sip_pvt_unlock(p);
 		}
@@ -7501,8 +7507,11 @@
 						transmit_provisional_response(p, "183 Session Progress", &p->initreq, TRUE);
 						ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
 					}
-					p->lastrtptx = time(NULL);
-					res = ast_rtp_instance_write(p->trtp, frame);
+					if (p->invitestate > INV_EARLY_MEDIA || (p->invitestate == INV_EARLY_MEDIA &&
+										 ast_test_flag(&p->flags[0], SIP_PROGRESS_SENT))) {
+						p->lastrtptx = time(NULL);
+						res = ast_rtp_instance_write(p->trtp, frame);
+					}
 				}
 			}
 			sip_pvt_unlock(p);
@@ -7930,8 +7939,14 @@
 		    !ast_test_flag(&p->flags[0], SIP_PROGRESS_SENT) &&
 		    !ast_test_flag(&p->flags[0], SIP_OUTGOING)) {
 			p->invitestate = INV_EARLY_MEDIA;
-			transmit_provisional_response(p, "183 Session Progress", &p->initreq, TRUE);
-			ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
+			/* SIP_PROG_INBAND_NEVER means sending 180 ringing in place of a 183 */
+			if (ast_test_flag(&p->flags[0], SIP_PROG_INBAND) != SIP_PROG_INBAND_NEVER) {
+				transmit_provisional_response(p, "183 Session Progress", &p->initreq, TRUE);
+				ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
+			} else if (ast_channel_state(ast) == AST_STATE_RING && !ast_test_flag(&p->flags[0], SIP_RINGING)) {
+				transmit_provisional_response(p, "180 Ringing", &p->initreq, 0);
+				ast_set_flag(&p->flags[0], SIP_RINGING);
+			}
 			break;
 		}
 		res = -1;
@@ -23111,6 +23126,8 @@
 			if (!req->ignore && p->owner) {
 				/* Queue a progress frame only if we have SDP in 180 or 182 */
 				ast_queue_control(p->owner, AST_CONTROL_PROGRESS);
+				/* We have not sent progress, but we have been sent progress so enable early media */
+				ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
 			}
 			ast_rtp_instance_activate(p->rtp);
 		}
@@ -23194,6 +23211,8 @@
 			if (!req->ignore && p->owner) {
 				/* Queue a progress frame */
 				ast_queue_control(p->owner, AST_CONTROL_PROGRESS);
+				/* We have not sent progress, but we have been sent progress so enable early media */
+				ast_set_flag(&p->flags[0], SIP_PROGRESS_SENT);
 			}
 			ast_rtp_instance_activate(p->rtp);
 		} else {