--- main/codec_builtin.c	(Asterisk 13.6.0)
+++ main/codec_builtin.c	(working copy)
@@ -594,7 +594,7 @@
 	.type = AST_MEDIA_TYPE_AUDIO,
 	.sample_rate = 8000,
 	.minimum_ms = 30,
-	.maximum_ms = 30,
+	.maximum_ms = 300,
 	.default_ms = 30,
 	.minimum_bytes = 50,
 	.samples_count = ilbc_samples,