TT#64300 don't attempt to transcode to an unsupported codec

Change-Id: Ib4bad65472139f214bbb3896c1f9df29cc8e140e

daemon/codec.c

@@ -653,7 +653,8 @@ next:
 			// if the sink does not support DTMF but we can receive it, we must transcode
 			// DTMF event packets to PCM. this requires all codecs to be transcoded to the
 			// sink's preferred destination codec.
-			if ((!transcode_dtmf && dtmf_payload_type == -1) || !pref_dest_codec)
+			if ((!transcode_dtmf && dtmf_payload_type == -1) || !pref_dest_codec
+					|| !handler->source_pt.codec_def || !pref_dest_codec->codec_def)
 				__make_passthrough_ssrc(handler);
 			else
 				__make_transcoder(handler, pref_dest_codec, output_transcoders, dtmf_payload_type);