Nintendo Roms slow

I have a nintendo emulator on my xbox. Now I downloaded some roms (games). Mario bros, life force and tecmo bowl. When I load mario bros, game play is very slow, as if it is on slow mo. Does anyone know why this happens. The other games work fine.

 

it is the emulator
it happens to me all the time
with the linux emulator it works fine

 

I am currently using xnes on my xbox. Do you know of a good nes emulator for the xbox that will play mario bros?

 

that is what i am using

i put linux on my xbox and used the linux nes emulator

 

I found another emulator that works better than xnes. Try FCE Ultra 1.6. This one doesn't ahve any problems. In some ways itz better.

 

i think i might have to try that