Well I've had a rake around and all I can come up with is change the internal 9V battery that lives under a small hatch on the bottom. If that dosen't work then it's mebbie time to abandon the thing. Bose aren't one bit embarrassed when it comes to charging for repairs.
It's amazing 'science' always seems to 'find' whatever it is funded for, and never the oppsite. Drich.