“Hey, I just got my letter from Activision in the mail. It has a letter explaining the problem with Guitar Hero 3’s sound issues and how to mail back my disc and how they will send me the new disc. It also has an envelope with stamps attached.”
Letter from Activision:

We understand that some customers have not been able to enjoy the full audio output in the Wii version of Guitar Hero III: Legends of Rock. Activision has worked with Nintendo to remaster the game and provide a replacement disc to customers with Dobly digital surround sound and other customers experiencing audio issues.

To receive a replacement disc for the Wii version of Guitar Hero III: Legends of Rock you must do the following:

1. Complete this form.
2. Mail the claim form along with your Guitar Hero III: Legends of Rock disc in the enclosed pre-paid disc mailer to the pre-printed address no later than August 21, 2008.

No replacement disc will be sent to you unless the original game disc and completed claim form are received with a postmark date of August 21, 2008 or earlier. Mailings with a postmark date later than August 21, 2008 will not be returned and you will not receive a replacement disc.

Do not send any packaging from the original Guitar Hero III: Legends of Rock game. Please send the game disc only.

When receipt of your original disc is confirmed, a replacement disc will be mailed to you. Please allow 3-4 weeks to receive a replacement disc. You can view the status of your disc replacement at activision.rebatestatus.com or by calling 888-788-4331.

Guitar Hero 3 Replacement Disc Form