diff --git a/lib/codeclib.c b/lib/codeclib.c
index 5e2082f38..f056c0a90 100644
--- a/lib/codeclib.c
+++ b/lib/codeclib.c
@@ -63,6 +63,8 @@ static int ilbc_decoder_input(decoder_t *dec, const str *data, GQueue *out);
 static const char *dtmf_decoder_init(decoder_t *, const str *, const str *);
 static int dtmf_decoder_input(decoder_t *dec, const str *data, GQueue *out);
 
+static int format_cmp_ignore(const struct rtp_payload_type *, const struct rtp_payload_type *);
+
 
 
 
@@ -396,6 +398,7 @@ static codec_def_t __codec_defs[] = {
 		.default_clockrate = 8000,
 		.default_channels = 1,
 		.default_fmtp = "0-15",
+		.format_cmp = format_cmp_ignore,
 		.codec_type = &codec_type_dtmf,
 		.support_encoding = 1,
 		.support_decoding = 1,
@@ -2276,3 +2279,9 @@ static int dtmf_decoder_input(decoder_t *dec, const str *data, GQueue *out) {
 
 	return 0;
 }
+
+
+
+static int format_cmp_ignore(const struct rtp_payload_type *a, const struct rtp_payload_type *b) {
+	return 0;
+}
diff --git a/lib/codeclib.h b/lib/codeclib.h
index fef9181c9..94f3c0498 100644
--- a/lib/codeclib.h
+++ b/lib/codeclib.h
@@ -71,6 +71,7 @@ typedef int packetizer_f(AVPacket *, GString *, str *, encoder_t *);
 typedef void format_init_f(struct rtp_payload_type *);
 typedef void set_enc_options_f(encoder_t *, const str *, const str *);
 typedef void set_dec_options_f(decoder_t *, const str *, const str *);
+typedef int format_cmp_f(const struct rtp_payload_type *, const struct rtp_payload_type *);
 
 
 
@@ -126,6 +127,7 @@ struct codec_def_s {
 	const int default_bitrate;
 	int default_ptime;
 	const char *default_fmtp;
+	format_cmp_f * const format_cmp;
 	packetizer_f * const packetizer;
 	const int bits_per_sample;
 	const enum media_type media_type;
diff --git a/lib/rtplib.c b/lib/rtplib.c
index 1c5c6dec6..037302a46 100644
--- a/lib/rtplib.c
+++ b/lib/rtplib.c
@@ -145,6 +145,10 @@ const struct rtp_payload_type *rtp_get_rfc_codec(const str *codec) {
 int rtp_payload_type_cmp(const struct rtp_payload_type *a, const struct rtp_payload_type *b) {
 	if (rtp_payload_type_cmp_nf(a, b))
 		return 1;
+	if (a->codec_def && a->codec_def == b->codec_def) {
+		if (a->codec_def->format_cmp)
+			return a->codec_def->format_cmp(a, b);
+	}
 	if (str_cmp_str(&a->format_parameters, &b->format_parameters))
 		return 1;
 	return 0;
diff --git a/t/auto-daemon-tests.pl b/t/auto-daemon-tests.pl
index 3632f619b..6e9debdef 100755
--- a/t/auto-daemon-tests.pl
+++ b/t/auto-daemon-tests.pl
@@ -36,10 +36,257 @@ my ($sock_a, $sock_b, $sock_c, $sock_d, $port_a, $port_b, $ssrc, $resp,
 
 
 
-# inject DTMF with mismatched codecs
+if (0) {
+
+# GH 1098
+
+new_call;
+
+offer('gh 1098', {
+	codec => {
+		mask => ['all'],
+		transcode => ['G722', 'AMR-WB/16000/1///mode-set--0,1,2;mode-change-period--2;mode-change-capability--2/dtx--1', 'AMR', 'PCMA', 'telephone-event'],
+	}
+}, <<SDP);
+v=0
+o=- 3812713289 3812713289 IN IP4 foo.bar.com
+s=-
+c=IN IP4 1.1.1.1
+t=0 0
+m=audio 40732 RTP/AVP 111 108 8 101 96
+a=ptime:20
+a=rtpmap:111 AMR-WB/16000
+a=fmtp:111 mode-set=0,1,2; mode-change-period=2; mode-change-capability=2
+a=rtpmap:108 AMR/8000
+a=fmtp:108 mode-set=7
+a=rtpmap:8 PCMA/8000
+a=rtpmap:101 telephone-event/16000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-15
+a=fmtp:101 0-15
+----------------------------------
+v=0
+o=- 3812713289 3812713289 IN IP4 foo.bar.com
+s=-
+c=IN IP4 203.0.113.1
+t=0 0
+m=audio PORT RTP/AVP 9 96 108 8 101 96
+a=rtpmap:9 G722/8000
+a=rtpmap:96 AMR-WB/16000
+a=rtpmap:108 AMR/8000
+a=rtpmap:8 PCMA/8000
+a=rtpmap:101 telephone-event/16000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 mode-set=0,1,2;mode-change-period=2;mode-change-capability=2
+a=fmtp:108 mode-set=7
+a=fmtp:101 0-15
+a=fmtp:96 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+answer('gh 1098', {
+	flags => ['single-codec'],
+}, <<SDP);
+v=0
+o=FreeSWITCH 1603706241 1603706242 IN IP4 3.3.3.3
+s=FreeSWITCH
+c=IN IP4 3.3.3.3
+t=0 0
+m=audio 18248 RTP/AVP 9 96
+a=rtpmap:9 G722/8000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-16
+a=silenceSupp:off - - - -
+a=ptime:20
+a=rtcp:18249 IN IP4 3.3.3.3
+----------------------------------
+v=0
+o=FreeSWITCH 1603706241 1603706242 IN IP4 3.3.3.3
+s=FreeSWITCH
+c=IN IP4 203.0.113.1
+t=0 0
+m=audio PORT RTP/AVP 111 101
+a=silenceSupp:off - - - -
+a=rtpmap:111 AMR-WB/16000
+a=rtpmap:101 telephone-event/16000
+a=fmtp:111 mode-set=0,1,2; mode-change-period=2; mode-change-capability=2
+a=fmtp:101 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
 
 new_call;
 
+offer('gh 1098', {
+	codec => {
+		mask => ['all'],
+		transcode => ['G722', 'AMR-WB/16000/1///mode-set--0,1,2;mode-change-period--2;mode-change-capability--2/dtx--1', 'AMR', 'PCMA', 'telephone-event'],
+	}
+}, <<SDP);
+v=0
+o=- 3812713289 3812713289 IN IP4 foo.bar.com
+s=-
+c=IN IP4 1.1.1.1
+t=0 0
+m=audio 40732 RTP/AVP 111 108 8 101 96
+a=ptime:20
+a=rtpmap:111 AMR-WB/16000
+a=fmtp:111 mode-set=0,1,2; mode-change-period=2; mode-change-capability=2
+a=rtpmap:108 AMR/8000
+a=fmtp:108 mode-set=7
+a=rtpmap:8 PCMA/8000
+a=rtpmap:101 telephone-event/16000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-15
+a=fmtp:101 0-15
+----------------------------------
+v=0
+o=- 3812713289 3812713289 IN IP4 foo.bar.com
+s=-
+c=IN IP4 203.0.113.1
+t=0 0
+m=audio PORT RTP/AVP 9 96 108 8 101 96
+a=rtpmap:9 G722/8000
+a=rtpmap:96 AMR-WB/16000
+a=rtpmap:108 AMR/8000
+a=rtpmap:8 PCMA/8000
+a=rtpmap:101 telephone-event/16000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 mode-set=0,1,2;mode-change-period=2;mode-change-capability=2
+a=fmtp:108 mode-set=7
+a=fmtp:101 0-15
+a=fmtp:96 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+answer('gh 1098', {
+	codec => {
+		strip => ['all'],
+		offer => ['PCMA'],
+	}
+}, <<SDP);
+v=0
+o=FreeSWITCH 1603707514 1603707515 IN IP4 3.3.3.3
+s=FreeSWITCH
+c=IN IP4 3.3.3.3
+t=0 0
+m=audio 17766 RTP/AVP 8 96
+a=rtpmap:8 PCMA/8000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-16
+a=silenceSupp:off - - - -
+a=ptime:20
+a=rtcp:17767 IN IP4 3.3.3.3
+----------------------------------
+v=0
+o=FreeSWITCH 1603707514 1603707515 IN IP4 3.3.3.3
+s=FreeSWITCH
+c=IN IP4 203.0.113.1
+t=0 0
+m=audio PORT RTP/AVP 8
+a=silenceSupp:off - - - -
+a=rtpmap:8 PCMA/8000
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+
+
+new_call;
+
+offer('gh 1098', {
+	codec => {
+		mask => ['all'],
+		transcode => ['G722', 'AMR-WB/16000/1///mode-set--0,1,2;mode-change-period--2;mode-change-capability--2/dtx--1', 'AMR', 'PCMA', 'telephone-event'],
+	}
+}, <<SDP);
+v=0
+o=- 3812713289 3812713289 IN IP4 foo.bar.com
+s=-
+c=IN IP4 1.1.1.1
+t=0 0
+m=audio 40732 RTP/AVP 111 108 8 101 96
+a=ptime:20
+a=rtpmap:111 AMR-WB/16000
+a=fmtp:111 mode-set=0,1,2; mode-change-period=2; mode-change-capability=2
+a=rtpmap:108 AMR/8000
+a=fmtp:108 mode-set=7
+a=rtpmap:8 PCMA/8000
+a=rtpmap:101 telephone-event/16000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-15
+a=fmtp:101 0-15
+----------------------------------
+v=0
+o=- 3812713289 3812713289 IN IP4 foo.bar.com
+s=-
+c=IN IP4 203.0.113.1
+t=0 0
+m=audio PORT RTP/AVP 9 96 108 8 101 96
+a=rtpmap:9 G722/8000
+a=rtpmap:96 AMR-WB/16000
+a=rtpmap:108 AMR/8000
+a=rtpmap:8 PCMA/8000
+a=rtpmap:101 telephone-event/16000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 mode-set=0,1,2;mode-change-period=2;mode-change-capability=2
+a=fmtp:108 mode-set=7
+a=fmtp:101 0-15
+a=fmtp:96 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+answer('gh 1098', {
+	codec => {
+		strip => ['all'],
+		offer => ['PCMA', 'telephone-event'],
+	}
+}, <<SDP);
+v=0
+o=FreeSWITCH 1603707514 1603707515 IN IP4 3.3.3.3
+s=FreeSWITCH
+c=IN IP4 3.3.3.3
+t=0 0
+m=audio 17766 RTP/AVP 8 96
+a=rtpmap:8 PCMA/8000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-16
+a=silenceSupp:off - - - -
+a=ptime:20
+a=rtcp:17767 IN IP4 3.3.3.3
+----------------------------------
+v=0
+o=FreeSWITCH 1603707514 1603707515 IN IP4 3.3.3.3
+s=FreeSWITCH
+c=IN IP4 203.0.113.1
+t=0 0
+m=audio PORT RTP/AVP 8 96
+a=silenceSupp:off - - - -
+a=rtpmap:8 PCMA/8000
+a=rtpmap:96 telephone-event/8000
+a=fmtp:96 0-16
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+}
+
+
+
+
+
+# inject DTMF with mismatched codecs
+
 ($sock_a, $sock_b) = new_call([qw(198.51.100.11 3000)], [qw(198.51.100.11 3002)]);
 
 ($port_a) = offer('inject, U/A offer',