i'm wondering if the output tubes are the only reason why i would be hearing faint static - the you hear when tuning a dial radio - in one channel.  i had this problem with a set of output tubes and i swapped them out and it seemed to fix the problem.  however the problem seems to have returned in the same channel albeit much less noticeable. thanks in advance.

Oh boy…I was dealing with a noise issue that drove me nuts.  CAJames helped my isolate my issue that was tube related amongst other issues.   Check your interconnects….maybe them being in a certain orientation is causing the static.  Hopefully I you can figure it out without causing you go nuts.