Update: I tried to check it through the retropie audio settings and found an option called "enable Pulse Audio" once I did that the message disappeared. I've yet to test it with bluetooth but I think (and hope) that solved the issue.
Thanks for your help!
@stoo Having lots of differences between FBNeo & MAME for system16 based hardware isn't surprising, system16 is a historical driver for Final Burn (first FB driver and first emulator to run that hardware, the emulator's name is actually based on "After Burner"), current FBNeo driver is built upon that initial driver. You should report the glitches at https://github.com/finalburnneo/FBNeo/issues, we can't fix what we don't know about :)
If SNES runs at 10 FPS on a Zero, I wouldn't be surprised if N64 emulation set it on fire.
You can run SNES using the older snes9x cores and performance is acceptable as long as you aren't trying to run superfx games. Even psx performance on the pi zero is not bad using the standalone emulator.
anything is possible, but tbh it looks like more truble than it will be worth.
obviusly you will need to remove some of the board and you will most likely also need a new control board for the screen and will therefore most likely not fit inside the old case either.
cosiddering all this and the fact that you had to ask if it was possible, i would say this is likely a job way above your skillset and not worth the efford, for you.
personally i would just get one of the many kits available.