Hi all— I’ve read what feels like every post I can find about the CPR having him when turning the reverb past 3 on the dial. I too am having this issue and looking to get some advice moving forward. First of all, I got the amp used and really love it sans the reverb hum so I can’t return it. What I’ve done: Retubed the amp with TAD, Gold Lion and Mullard tubes (except for the rectifier tube). Bought a better Reverb cable Swapped the tank 180 degrees Took the tank out of the unit to see if it was being affected by anything in the amp When I unplug the tank, I get no gum at all. When I use the footswitch to disengage the reverb, then turn the nob, no hum happens. My thinking is that this seems like a Reverb tank issue since the hum is not present when on 10 and the tank is disengaged. Would you guys suggest a different Reverb tank? If so, what brand? Should I have a tech look at modifying something?