Hello @quantumguru,
This Apple provided program “SideBySideToMVHEVC” removes the audio track from our videos resulting in useless content.
Yes, that sample app does not account for anything other than the first visual track of the source asset. That sample app "demonstrates the process for converting side-by-side video files to MV-HEVC, encoding the output as a QuickTime file" (emphasis added), it is not intended to be used directly as a conversion tool.
I recommend the following:
- File an enhancement request using Feedback Assistant to request a tool that has the functionality you are looking for.
- Try modifying that sample app to build a tool that has the functionality you are looking for.