Just picked up a used Wii for a tenner, I only wanted it for the Wiimote and Nunchuck. Anyway, I thought I might as well mod the Wii just for the hell of it. The modding was pretty straight forward, so I decided to install a few Virtual Console WADS. This is where I started having problems...

I installed a few to try:
N64
Mario 64
Mario Kart 64

SNES
Super Mario World
Super Mario Kart
Super Metroid

Megadrive
Sonic 1-3

Once I'd rebooted, the games show up as normal, the N64 games have bad choppy sound, like the game isn't running fast enough. I tried changing the TV settings to 60Hz, this worked for Mario 64, but not Mario Kart 64. I've tried various different versions, PAL, NTSC and different releases, none work correctly.

No SNES or Megadrive games work at all, I'm pretty stumped at the moment, I've had no problem running N64 roms on my kid's consoles, haven't tried any other platforms. Wiiware, and both original Wii games and backups work fine.

I know this is a longshot, but does anyone know how to fix the VC roms issue?