diff --git a/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn.h b/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn.h
index 80dc73f0fa..b369deae1f 100644
--- a/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn.h
+++ b/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn.h
@@ -80,6 +80,8 @@ typedef enum {
 	FLAG_ACTIVATING			= (1 << 10),
 	/* Used when we receive an ALERT msg + inband tones ready */
 	FLAG_MEDIA_READY		= (1 << 11),
+	/* Set when we already sent a Channel ID IE */
+	FLAG_SENT_CHAN_ID		= (1 << 12),
 } sngisdn_flag_t;
 
 
diff --git a/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn_support.c b/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn_support.c
index 23fe08b983..08e5984a4f 100644
--- a/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn_support.c
+++ b/libs/freetdm/src/ftmod/ftmod_sangoma_isdn/ftmod_sangoma_isdn_support.c
@@ -821,9 +821,17 @@ ftdm_status_t set_prog_ind_ie(ftdm_channel_t *ftdmchan, ProgInd *progInd, ftdm_s
 
 ftdm_status_t set_chan_id_ie(ftdm_channel_t *ftdmchan, ChanId *chanId)
 {
+	sngisdn_chan_data_t *sngisdn_info = (sngisdn_chan_data_t*)ftdmchan->call_data;
 	if (!ftdmchan) {
 		return FTDM_SUCCESS;
 	}
+
+	if (ftdm_test_flag(sngisdn_info, FLAG_SENT_CHAN_ID)) {
+		/* Indicate channel ID only in first response */
+		return FTDM_SUCCESS;
+	}
+	ftdm_set_flag(sngisdn_info, FLAG_SENT_CHAN_ID);
+	
 	chanId->eh.pres = PRSNT_NODEF;
 	chanId->prefExc.pres = PRSNT_NODEF;
 	chanId->prefExc.val = IN_PE_EXCLSVE;