Avidemux+cannot+use+that+file+as+audio+track [hot]

Avidemux is an excellent, lightweight open-source tool for quick video editing, cutting, and muxing. However, importing an external audio file often triggers a frustrating compatibility roadblock:

Avidemux has a complex history with AAC audio due to licensing issues. While it can often play AAC audio inside a video file, it may struggle to import a standalone AAC/M4A file as an external track if the specific internal decoder isn't loaded.

The audio file's technical specs do not match what the video container supports.

: Avidemux cannot use audio files already "wrapped" in a container like .m4a or .mp4 as an external track. It lacks the internal demuxers to strip these for external loading. avidemux+cannot+use+that+file+as+audio+track

To prevent encountering "Cannot use that file as audio track" in the future:

You are trying to load a MP3 file into a project where Audio Output is set to "AAC" . Avidemux tries to copy the MP3 as AAC, which is impossible. Alternatively, you load a FLAC file when Audio Output is set to "Copy" while outputting to an MP4 container (which doesn’t support FLAC).

If you are still experiencing issues after trying these conversion steps, I can help you investigate further. Please let me know: Avidemux is an excellent, lightweight open-source tool for

Ensure the video is opened first, then select the audio track.

If you are still experiencing issues, consider examining the file with to determine its exact codec and container structure.

Think of it like this: A container (like MP4) is a cardboard box used for shipping. Inside that box, you can put a video stream (a Blu-ray movie) and an audio stream (a music CD) together. When Avidemux opens a video file, it knows how to open the whole box and unpack both items. The audio file's technical specs do not match

To help narrow down the best solution for your project, let me know:

Now retry Step 5 with the WAV file. Avidemux will always accept a standard WAV file when Audio Output is set to PCM or Copy (if the container allows it).

In Audio > Main Track , check Shift and Delay . Don't change them; just toggle the checkbox. Sometimes this forces Avidemux to recalculate the duration. Alternatively, use Audacity to trim/silence the audio to exactly match the video length (down to the millisecond).