I am finally back in the Virtual Boy business.
Got myself a japanese system and also a spare head unit.

This head unit has problems with the Sound. The left speaker does not work. I opened the VB to check for loose cables or so but that was all fine. The speaker itself is also okay.
It seems there is a problem with the AMP board.
Is this a common problem? Old Caps?

Maybe it’s the left audio output pin on the VSU that’s not working?

Broken Sound chip?

There’s a guy on EBay who breaks VB’s into parts and sells them separately.

I’ve fixed a couple of consoles pretty cheaply using his parts.

i say just replace it. but try a bit of contact cleaner on the game connection pins first and see if that fixes it. somtimes the pins could be dirty stopping sound from getting to the speaker

https://www.ebay.com/itm/Nintendo-Virtual-Boy-3D-VB-L-R-SPEAKERS-repair-parts/123168592243?hash=item1cad6b9173:g:25AAAOSwDZ1bErNu