diff --git a/nginx-rtmp-module/src/ngx_rtmp_codec_module.c b/nginx-rtmp-module/src/ngx_rtmp_codec_module.c
index 52b71e2f..9ac8a7ea 100644
--- a/nginx-rtmp-module/src/ngx_rtmp_codec_module.c
+++ b/nginx-rtmp-module/src/ngx_rtmp_codec_module.c
@@ -580,30 +580,31 @@ ngx_rtmp_codec_av(ngx_rtmp_session_t *s, ngx_rtmp_header_t *h, ngx_chain_t *in)
     }
 
     /* no conf */
-    if (h->type == NGX_RTMP_MSG_VIDEO
-        && !ngx_rtmp_is_codec_header(ctx->video_codec_id, in))
+    if (!ngx_rtmp_is_codec_header(ctx->video_codec_id, in))
     {
-        if (ctx->video_captions_tries <= 0) {
-            return NGX_OK;
-        }
+        if(h->type == NGX_RTMP_MSG_VIDEO) {
+            if (ctx->video_captions_tries <= 0) {
+                return NGX_OK;
+            }
 
-        switch (ctx->video_codec_id) {
+            switch (ctx->video_codec_id) {
 
-        case NGX_RTMP_VIDEO_H264:
-        case NGX_RTMP_CODEC_FOURCC_HVC1:
-        case NGX_RTMP_CODEC_FOURCC_HEV1:
-            if (ngx_rtmp_codec_detect_cea(s, in)) {
-                ctx->video_captions = 1;
-                ctx->video_captions_tries = 0;
+            case NGX_RTMP_VIDEO_H264:
+            case NGX_RTMP_CODEC_FOURCC_HVC1:
+            case NGX_RTMP_CODEC_FOURCC_HEV1:
+                if (ngx_rtmp_codec_detect_cea(s, in)) {
+                    ctx->video_captions = 1;
+                    ctx->video_captions_tries = 0;
 
-            } else {
-                ctx->video_captions_tries--;
-            }
+                } else {
+                    ctx->video_captions_tries--;
+                }
 
-            break;
+                break;
 
-        default:
-            ctx->video_captions_tries = 0;
+            default:
+                ctx->video_captions_tries = 0;
+            }
         }
 
         return NGX_OK;