Alright, so I got back from travel a while ago, but let this fall by the wayside as things have been busy. Sorry. Attached is a picture of the inside of the amp from when I built it. Thinking about this here at work it came to me that I shielded the input connection to that tone pot, so when the tone pot is sending frequencies to ground, it’s also putting them over the shielded portion of the input. Do you think this could cause it? It seems that it would make sense that when the tone is full up, it’s not shedding any freqs to ground or into that shield connection. I may try to re-do the input connection and use a better shield. Thoughts? Input connection is on the top left of the picture with the small clear covered wire going to the tone pot.