Mechanical licence

Recording your own version of a song somebody else wrote needs a mechanical licence from the publisher. In the United States that licence is compulsory, so the publisher cannot say no; you pay the statutory rate and go ahead. Elsewhere the equivalent runs through collecting societies.

The trap is the word audio. A mechanical covers a recording on its own, and putting music together with moving pictures is a synchronisation matter, a separate permission nobody is obliged to grant. That is why a cover uploaded to YouTube can still be claimed, muted or demonetised even when the mechanical side was handled properly, and why cover channels usually work through a service that clears both.