I tried a few different things last night and the problem was intermittent. I swapped out all the tubes and the noise issue is remedied so far. If it's not tube related I'll address the issue with a technician
Here’s some further info on my tests. Swapping out each of the preamp tubes with another tube didn’t solve the problem. The noise is there when I run a single cable in the loop with no pedals, so it’s amp-related and not a result of the pedals that I was using. As soon as I break the circuit...
I just configured my pedal board so the mod pedals (delay, chorus, volume pedal) run in the effect loop of my F-30 (4 cable method). After hooking it up for the first time, I'm getting a unacceptable amount of white noise from the amp, that sounds like FM radio static. When I bypass (unplug)...
Just wanted to report that I'm currently having good success getting a classic rock overdrive from my F30 amp by swapping the 12AX7 tube in V2 with a 12AU7. V1 is still a 12AX7.