Snes9x.com

Umh how could i explain it. Hmmh first two levels sound was ok and nothing happened but when i got to mushroom kingdom this strange problem started.
Problem is that the music and sound went from completely perfect to horribly scratchy. Don't know if it continues after the mushroom kingdom but still if it continues then it will bother me alot. Is this normal? First i thought maybe i have so shitty computer that it just doesn't run snes games that well because i haven't updated my computer since 2005 but when i turned fps on it showed 60/60.

What audio card do you have?
Which operating system are you running?
What version of Snes9x do you have?

Well, it might be something with your computer. First, does this just happen with MArio RPG, or with any game, and, if only Mario RPG, try other "demanding games", like Super Mario Kart, or any other games typically resource-demanding, and see if it also affects those.

I had once solved such problems, but I forget how, and these newer systems change so much and actually get worse to deal with, IMO. Finally, you could try going into sound settings and lowering the output rate and see if it can keep up now.

BTW, is the issue specifically with the Msuhroom Kingdom thingy you mentioned? if you playa while elsewhere, will it happen then? If you make a save state right before your issue, close and reopen the emulator, and load the save, does it happen against once you enter the affected area, or does it take a little time?