on arcade games in its intended resolution there is black bars at top and bottom because its on 1280x1024 when I try drop the resolution lower on launch options the game wont load up for some reason, just the sound and a black screen.

I can go into option during the game with the 1280x1024 and change the screen to fit but I have to do that for all games it's a bit annoying.

Retropie 4.6 on a raspberry pi 3B with a 128gb Card.

@jjapes Just update mupen64plus via retropie-setup.

@meleu Thank you for your answer.

I've tried it again with all buttons and both methods on the controller. Holding and tapping.
It only works with the 'A'-Button on my keyboard.

I'll try to remove the keyboard and the keybinds for it and see it that helps.

@edmaul69 Sweet, I was looking for something like this before. After some testing I have noticed something. When turning on the Pi or rebooting it with cables plugged in for different controllers, I can have them set in their respective ports 0,1,2 etc and my PS3 controller will not become JS0 it will become whatever light is shown on the PS3 controller i.e. JS1 it will be player 1 on the controller light.

If I reboot and unplug every wire so the USB ports are empty and connect it to blue tooth as it's booting, my controller blinks for a bit then stops and shows no lights. I've had this happen before on macs and the controller still works even though it's not indicating a "player." When the controller is like this it is JS0.

So it appears that if you want your PS3 controller to be JS0 and not JS1-4 potentially, you need to connect it as it's booting through bluetooth with nothing else plugged in the USB ports.

@raktfranhjartat Please do not post a support request without first reading and following the advice in https://retropie.org.uk/forum/topic/3/read-this-first (Please start a new topic).

The option is in the runcommand entry in the RetroPie menu on Emulation Station.

@An0nymouse go into RetroPie Set up. Choose Configuration / tools. Choose runcommand. Ensure Launch menu is enabled. Also ensure joystick control is enabled if you want to use it rather than a keyboard.