Left bumper button works intermittently and sometimes not at all.

I've been having the same problem for about a year now. You're the first other person I've seen having the same issue.

In addition, I've tried changing the rubber pads of the bumpers and triggers and cleaning the contacts with alcohol. On the software side, I've tried every single FW version, using both BT, 2.4G and USB on multiple devices / OSs (Windows, Linux, Android). None of these have fixed the issue though.

I have this issue with my right bumper. Sounds more like a hack then anything else, but I plugged the controller on my PC with Cable, opened the 8bitdo Ultimate Software, and changed the trigger sensibility it's "considered" fully pressed, at like 80% of the press. So that way the press is always registered.

Also, with that software you can diagnosed what's happening. For me, when I fully press, it shows that's pressed at around 95% and it "flickers" (the bar is moving up and down).

Note: I'm in the process of opening mine and attempt a repair (probably cleanup dirt or something). I will update when it's done.

@poudigne Do you mean that your trigger or bumper is broken now? Since I'd think adjusting the trigger (R2) wouldn't affect the bumper (R1).

@someone7618 ho yeah the trigger is broken, not bumper. I misread, my bad.