appriciate it's a very old topic but in case anyone perseveres with glitchy Kilbunr v1 ... I had problems with main power supply which was due to one of the rectifier diods described and resolved [post|718627|here]
the speaker worked for a about a week then stopped responding to Bluetooth or aux inputs - no music from the speaker, only static noise and cracking sounds similar to Atilla's video.
I could not find any signs of corrosion but there were few tiny yellow droplets in the proximity of the capacitors. Fiddled a bit with cleaning but no luck. Eventually, after switching between AUX and Bluetooth the music (almost magically) reappeared. Statick noise and cracking sound on Bluetooth remained and from time to time it stops playing. I switch between AUX and Bluetooth few times , after that the music comes back. I've no idea what that could be - there are no obvious signs of damage on the board.
Wonder if anyone may have an insight or an advice to share. I've been fixing this speaker for a few years now - it's way beyond it's economic value but turned into a hobby sort of :)