My four month old Bose QC25 Quiet Comfort 25 Acoustic Noise Cancelling Headphones stopped working. The battery light started blinking, so I replaced the battery. The battery is fresh, and there is no corrosion - I even cleaned the terminals with vinegar just in case. I stupidly bought these on ebay - new - but realize now I did not get a warranty sheet and never thought of doing anything about it at the time. Any suggestions? Thank you.