Super MVS Converter II - Sound Issue?

I've just been playing a Multi 150-in-1 cart on my Neo Geo AES using the Super MVS Converter II and I've noticed a strange sound issue.

The sound plays fine, but occasionally the music will go loud for a brief moment, then die out again. The music also sounds slightly garbled on certain games.

Is this an issue with the converter, or is it down to the cheap nature of the 150-in-1 cart? I don't have any other MVS games to test with the converter, and I know it can't be the machine because the issue isn't present on my AES games.

could be either or both. Most of the issues with the converter tend to be not running the game at all, or are with regard to scaling. The 150 in 1 does have several issues with many of the games but I don't know which problems are known for which games.