First things first, they look like Beats, but I’m pretty sure these are knockoffs. Nonetheless, they sound pretty good, and I picked them up at Goodwill for a steal and love a challenge, so if someone is interested on taking on this electronics mystery with me I’d be incredibly grateful.
Context: I’ve tinkered on and off with consumer electronics for a while now, am okay at soldering and have an okay knowledge of how more basic circuits work. Otherwise, I'm pretty beginner but generally a quick learner and would be happy to try any of your suggestions.
The previous owner attempted to replace the AAA battery holding component with a rechargeable lithium ion battery - only problem was there was no way to charge the battery. Not a huge deal, fixed the headphones to run on AAAs again as they were originally intended. That said, pressing and holding the power button powers the headphones on, but also is the Bluetooth connection button on the board (image at the imgur link below) there is an icon for both the connection functionality and the power around the same button. The headphones power on, work, and sound great when you're holding the button down, but once you let go they turn off. So, it’s a momentary switch with no latch to keep it held down - not ideal.
That said, I’ve tested jumping the switch so it gets constant power without holding the button down, and while the headphones power on, connect to my phone, and work, because it seems the power button and bluetooth button are one in the same, the headphones continue to look for Bluetooth devices and makes a periodic and infuriating beeping sound about every fifteen seconds. Based on the pictures of the board below (pictured with, and without button attached) can anyone figure out what the problem might be? Or point me in the right direction for further tests to run?
Front of the board, with buttons.
Front of the board, with power/bluetooth button removed
Back of the board, held upright with power/bluetooth button side up