Need Help Retroarch slow and crashing

I’m having trouble with the N64 games. All of them are slow. The audio and video are choppy. Same goes for the psx games. The psp emulator is the weirdest one. Spiderman 2 works fairly well, but tekken 5 and Prince of persia cause retroarch to crash. I’ve turned VSync on and off and it has no effect. Any ideas on what I can do?