diff --git a/src/data/beos_mime/audio/mp4 b/src/data/beos_mime/audio/mp4
index f1199f45ef..890ea0ffae 100644
--- a/src/data/beos_mime/audio/mp4
+++ b/src/data/beos_mime/audio/mp4
@@ -8,7 +8,6 @@ resource(2, "META:S:DESC") #'MSDC' "MP4 Sound File";
 resource(3, "META:PREF_APP") #'MSIG' "application/x-vnd.Haiku-MediaPlayer";
 
 resource(4, "META:EXTENS") message(234) {
-	"extensions" = "mp4",
 	"extensions" = "m4a",
 	"type" = "audio/mp4"
 };
diff --git a/src/data/beos_mime/video/mp4 b/src/data/beos_mime/video/mp4
index 5566f463b8..6c666c854d 100644
--- a/src/data/beos_mime/video/mp4
+++ b/src/data/beos_mime/video/mp4
@@ -7,6 +7,7 @@ resource(2, "META:S:DESC") #'MSDC' "MP4 Movie";
 
 resource(3, "META:EXTENS") message(234) {
 	"extensions" = "mp4",
+	"extensions" = "m4v",
 	"type" = "video/mp4"
 };