Audio channels reversed on integrated speakers 40xx-H

[trr]

Knulli build version

firefly 2024/12/04 03:10

Your architecture

RG40xx-H

Issue description

Audio channels are reversed, left comes right from speaker and right comes from left speaker.

With 3.5mm headphones connected, audio channels are correct.

Detailed reproduction steps

Launch 240p test suite in Mega Drive emulator. (I used version MD_Genesis-1.30)
Go to audio tests, sound test
Set to left or right channel on third row down, go back up to first row and play some notes by selecting the numbers.

Note, the select button for this test suite is Y on this device.

Details of any attempts to fix this yourself

Setting emulator to mono mode in core settings successfully causes mono audio.

Details of any modifications you have made to Knulli.

No mods, pretty much all defaults.

Logs and data

Core is Genesis Plus GX v1.7.4-30fe82
On Retroarch 1.19.1

Since channels are correct on headphones, it suggests the issue is not related to the emulator or software in use and is a device issue, whether hardware or audio stack I don't know.

If this is a hardware thing I imagine fixing it is going to be a pain due to needing to detect when headphones are connected or disconnected and swap them accordingly.