I've never really experienced any problems with my amps before so perhaps there is an obvious solution. If so I apoligize in advance.

I'm playing through a year-old Peavey VK112 that is in every way, stock (tubes and all) with a Fender Jaguar AV 1962, also stock with the exception of a bridge replacement. A day or two ago I started noticing, while rehearsing, that when playing high-pitched notes (the higher the worse), I get an extremely fuzzy thud that accompanies my note that gets louder as I do (either by actually turning the amp up or by physically playing louder), at higher volumes all but entirely drowning out my playing. I can't exactly describe the sound it makes but at higher volumes playing shot notes produces a sound equivelant to what you might hear when being punched in the face.
Of relevance is that I play with a LOT of treble -- I employ the bass cut on the Jaguar itself (which, in itself, has 1M pots), use the "bright" button on the amp itself as well as having the treble EQ'ed anywhere from 8 to 10. However, I've been doing this a long time with no problems. My lead channel is EQed in a simillar way and I get no such sound on the lead channel. As would be expected, playing with just the bridge pickup makes the problem significantly worse and is where the problem is most notable (which is unfortunate because there are quite a few songs in which that is my de facto configuration).

So, people of UG, what do I do? Thanks in advance for your help.
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