diff --git a/photoapp/types.py b/photoapp/types.py
index 389f4e1..236de0c 100644
--- a/photoapp/types.py
+++ b/photoapp/types.py
@@ -25,6 +25,7 @@ known_mimes = {"image/png",
                "image/gif",
                "application/octet-stream-xmp",
                "image/x-canon-cr2",
+               "audio/mp4",
                "video/mp4",
                "video/quicktime"}
 
diff --git a/photoapp/utils.py b/photoapp/utils.py
index fa4dc5a..900eade 100644
--- a/photoapp/utils.py
+++ b/photoapp/utils.py
@@ -34,6 +34,7 @@ def mime2ext(mime):
             "image/gif": "gif",
             "application/octet-stream-xmp": "xmp",
             "image/x-canon-cr2": "cr2",
+            "audio/mp4": "mp4",
             "video/mp4": "mp4",
             "video/quicktime": "mov"}[mime]