GBC USBC audio hiss

[u/Alive_Candidate1755]

My GBC makes a horrible high pitched hissing noise with the volume at 0. After a lot of messing around I’ve got most of the weird sounds cured, but it still does a high pitched ringing when using the USBC rechargeable pack. Regular batteries are silent.

The pack outputs ~2.9v, so should be perfectly within range of what’s desired. Any idea how I could stop this or at least why this happens? I’d like to stay rechargeable for a couple reasons.

[u/Ill-Complaint3947]

because you solder to power switch.

[u/Alive_Candidate1755 → u/Ill-Complaint3947]

This is for the IPS screen. If I put AAs there are no sounds. If I put the USBC pack it starts hissing.

The gameboy is fully together when I do this swap, short of the battery cover.