I got a problem with all Guitar Hero games too... but its different... u can see my post here

http://gbatemp.net/index.php?showtopic=212005

All I can tell u its I updated my Wii to 4.2, and they were allright... maybe something else triggered your problem. Sry I cant help u

 

Someone?????

 

yea, OP ur not giving nearly enough info

how u launching games (usb or dvd, backup or original)

what cIOS are u using

when the game is playing, all it is using is the disk/disk image and the IOS... so whatever problem u are having, the solution is to reinstall the cIOS (maybe a different version, not sure what ur currently using) or get a better quality rip of the game

 

YEAH! I fixed it.

I decided to reinstall all cIOS etc. I always use FTPii, so i won't have to take the SD-card out. I'm glad I always do it like this, because now I found out my Wii wasn't connected to my Wi-Fi. I remember changing the password some weeks ago.

I changed the password in the Wi-Fi settings from my Wii, and it was back online. After this: no more problems! I think it's a huge bug in Guitar Hero games, because apparently the game is trying to connect to a server every minute! When it turns out the wrong Wi-Fi password is set, the game will lag for a second or so!

I hope someday someone wiih the same problem will read this :-)