It's unlikely to help, but you might want to try clearing the cache partition just in case something is messed up there.
- Power down phone
- Press and hold POWER-HOME-VOLUMEUP until phone vibrates and "entering recovery mode" comes up.
- Wait a bit until a menu comes up.
- Choose "clear cache" (I can't remember the exact wording, but it's ***NOT*** "factory reset and wipe data" that you want, and all the other options are about loading firmware from various sources).
- you'll get a little log message about the cache partition being reformatted, it takes very little time.
- Choose "restart phone"