I had an Arcam400 receiver after awhile the remote stopped responding, I read the manual instructions and found out that I had to press the AMP button on the remote for it to activate the remote again and after that it started to work, this happened occasionally but the AMP button served as an unlocking system for the remote for what I don't know but that's how it was it might help to look at your manual instructions.
good luck!
good luck!