Princeton Custom ‘68 RI - Resonance issue


Senior Stratmaster
Dec 28, 2016
Somehow my Fender Princeton’68 Custom Reissue has developed a new issue. At 440Hz, something starts to vibrate, and creates a buzz. The odd thing is that this just started yesterday, and nothing was changed or moved. The loudness of the buzz depends on the output volume, as one would expect. I can’t see anything loose inside the amp, and I removed all the stuff that was on it. What could it be?