diff --git a/conf/mime.types b/conf/mime.types
index c4ab45ec9..24e866e8f 100644
--- a/conf/mime.types
+++ b/conf/mime.types
@@ -62,6 +62,7 @@ types {
     audio/midi                            mid midi kar;
     audio/mpeg                            mp3;
     audio/ogg                             ogg;
+    audio/x-m4a                           m4a;
     audio/x-realaudio                     ra;
 
     video/3gpp                            3gpp 3gp;
@@ -69,6 +70,7 @@ types {
     video/mpeg                            mpeg mpg;
     video/quicktime                       mov;
     video/x-flv                           flv;
+    video/x-m4v                           m4v;
     video/x-mng                           mng;
     video/x-ms-asf                        asx asf;
     video/x-ms-wmv                        wmv;
diff --git a/src/http/modules/ngx_http_mp4_module.c b/src/http/modules/ngx_http_mp4_module.c
index 1140d9174..a6752123a 100644
--- a/src/http/modules/ngx_http_mp4_module.c
+++ b/src/http/modules/ngx_http_mp4_module.c
@@ -1882,7 +1882,7 @@ ngx_http_mp4_update_stts_atom(ngx_http_mp4_file_t *mp4,
     }
 
     entries = trak->time_to_sample_entries;
-    start_time = mp4->start * trak->timescale / 1000;
+    start_time = (uint64_t) mp4->start * trak->timescale / 1000;
 
     ngx_log_debug1(NGX_LOG_DEBUG_HTTP, mp4->file.log, 0,
                    "time-to-sample start_time:%uL", start_time);