I hate to throw an item away until I have tried to repair it, or at least investigated the problem. These JBL 500BT bluetooth headphones were cutting out on the left side, and it turns out the pressure from the spring contacts was enough to dislodge the small circuit board. It was not clipping into place very firmly. I'm not sure if this is a common problem or not, but the fix was simply to glue the board in place. I used a spritz of accelerator and my favourite cyanoacrylate, Loctite 480, but any super glue would work.