Have you checked your wireless channel settings? Considering it is wireless, there easily can be interference!
Go through all the channels and find one that is best for your area! I have not seen any signal issues with this router, maybe a bad antenna?
FW updates have been talked about through out the forum. It takes our region a while to get it since it is written, beta tested, revised, test again, etc., then translated and then sent here for final preperation and debugging before being posted.