Dang it. Besides Rockband deciding when IT wants to connect to XBOX Live or not, my guitar's up-strum is broken. This is actually a known problem with that input device.
The good news is that EA (the company) is sending me a replacement and empty box in the mail. I pay nothing. The process was very easy.
3 days ago I hoped online to visit EA's support site. In a few minutes they had already given me a UPS shipping number. All I have to do is wait for the new guitar to come and place my old guitar in the box. No cost to me.