Following issue occured, i have changed various file types, including .MP4 to use AIMP, since i have a lot of MP4 files in my playlists, mixed with mostly MP3. I know i could convert those files to MP3, but rather would like to keep the MP4 format, because of the artwork and label images, so. So i have moved MP4 from the video file type group to the music file type group. But i also have videos, that use MP4, and AIMP doesn't support any video. Any kind of idea, how to achieve this? It would be ideal to include some @ifpath rule in the "left double click" action, which is assigned to that music file type group, but that's not possible. I know, we can use some modifier key for different ways to play thte files, but maybe some sort of path switch is possible?
Audio-only MP4 files typically use a different file extension like .m4a or .aac to avoid this. The .mp4 extension is almost always only used for videos.
You could make something in Opus which examines the file contents to work out whether or not it has video, but it'd be quite complex, and would only solve the problem in Opus. Everything else would still be confused. I would use the .m4a extension for those audio files instead and avoid a lot of trouble.
Not a bad idea, it indeed works by just renaming MP4 to m4a. I also found John Zeman's button for mass renaming extensions, which is cool. Next thing would be to find a way to rename incoming files (mostly from YT) on the fly. Thanks! Another question, is it always safe to rename those files to m4a, or is MP4 some sort of container file, like AVI, and might leave some files broken? If not, that's perfect.
AFAIK it's save. Worst case is you just have to rename something back.
Sounds good. I have a full backup anyway. 
