Branch hotkeybtn Imposes USB Audio Issue on Amiberry

[Gemba]

I am using an RPI 3 with the hotkeybtn branch (Commit 840764e), two GPIO Controller configured, USB audio and Amiberry. For full setup and impact see my report at amiberry.

What I have noticed that described effect is gone when I remove the kernel module mk_arcade_joystick_rpi and start Amiberry with a non-GPIO controller, then Amiberry plays USB audio flawless with sound_frequency set to 44100 (default)).

ATM I can use the workaround since my hardware/arcade relies on the usage of a hotkey button.

Any clues/pointers which cause this lag when using the kernel module?