Kiwi

I have a 12 string with the same problem. Seller was a dick about returns and the problem was structural. Basically the manufacturer had mated a 12 string neck to a body that had been braced for a 6 string. That is, it needed double x bracing. Stewmac do a bridge doctor brace thing which attaches under the bridge and tensions off the tail block for US$22 so I may end up giving it a go.

Not yet, are they worth checking out? The market seems flooded these days.

I want to make 2 guitars: 1) A version of a PRS 509 but semi hollow with a bound neck and Yamaha MSG body shape. Limba chambered body, laminated flame maple and limba through neck. Not sure about pickups yet but i want to have a jazzy archtop sound in the neck, strat positions 2 and 4 and Les Paul in the bridge. Probably will get a set of custom wound Armstrongs. 2) A version of the Suhr Custom. Mahogany or limba solid body with set in flame maple neck, Lace HSS Sensors, TBX and EXG circuits. Both will have the ludicrously rare Wilkinson VS100C convertible trem, flamed maple carved tops front and back.