I’ve owned two Penguins and both have this problem. It’s not a loose screw, bridge rattle (Compton), etc. best way to repro is to solidly hit all 6 string harmonics at the 12th fret. I’ve tried touching various part to isolate it and moving the bride slightly sometimes helps. I use a solid brass Compton, so it’s not that. I suspect the pins the wood mount sits on are the cause. There is no way to access the underside of that, though. has anyone experienced and/or resolved this? My White Falcon does not have the problem, but both Midnight Sapphire 20115 Penguins I’ve had do. Bought a 2nd hoping the first one was a one off issue. Any advice would be appreciated. Or if you folks know of a Gretsch expert to go to in the San Jose, CA area, that would be great, too.