Avidemux Cannot Use That File As Audio Track -

If an MP3 still fails, the file might have a large header. Community experts suggest that stripping the first few kilobytes of the file (which often contain non-standard metadata) can sometimes allow Avidemux to "see" the actual audio frames. Supported External Audio Tracks

It should now load without the "Cannot use that file" error. avidemux cannot use that file as audio track