Some great news for Rock Band fans from Harmonix today. They wrote to tell us that gamers who are experiencing problems with their guitars (or any of the Rock Band instruments) should contact EA's customer support website and they will send out a replacement immediately.
"As sometimes happens when new products first go into manufacturing, we discovered an imperfection with the strum bar in an early production run of guitars that were shipped at launch. We've since identified and fixed the issue in all subsequent production runs of the guitars. If users are experiencing a problem with their guitars or any of the Rock Band instruments, they can visit the customer support website ( http://support.ea.com/rockband) and we will send a replacement immediately. Harmonix is dedicated to creating 100% customer satisfaction and to the users who have encountered any hardware issues, we are sorry for the hassle."