diff --git a/lib/codeclib.c b/lib/codeclib.c
index 4e693beaf..72b9741ff 100644
--- a/lib/codeclib.c
+++ b/lib/codeclib.c
@@ -210,6 +210,7 @@ static codec_def_t __codec_defs[] = {
 		.default_clockrate = 8000,
 		.default_channels = 1,
 		.default_ptime = 20,
+		.default_fmtp = "annexb=no",
 		.packetizer = packetizer_g729,
 		.bits_per_sample = 1, // 10 ms frame has 80 samples and encodes as (max) 10 bytes = 80 bits
 		.media_type = MT_AUDIO,