diff --git a/src/main/java/propertyFiles/MimeTypeDetectionByFileExtension.properties b/src/main/java/propertyFiles/MimeTypeDetectionByFileExtension.properties
index b9c9a661c80..2e7f763046f 100644
--- a/src/main/java/propertyFiles/MimeTypeDetectionByFileExtension.properties
+++ b/src/main/java/propertyFiles/MimeTypeDetectionByFileExtension.properties
@@ -15,7 +15,7 @@ m=text/x-matlab
 mat=application/matlab-mat
 md=text/markdown
 mp3=audio/mp3
-m4a=audio/x-m4a
+m4a=audio/mp4
 nii=image/nii
 nc=application/netcdf
 ods=application/vnd.oasis.opendocument.spreadsheet