Need Help! VHT Special 6 Ultra Combo

[An Kerreng]

Hi Softies and VHT Special 6 Ultra Combo
users,

I have a problem with my ULTRA channel.
Its so noisy and unplayable. Not sure whats
the problem. Its hissing and buzzing when
its over 1pm with volume at noon and boost
engaged.

Tubes: I swapped the tubes to JJ 6L6 and
JJ 12ax7.

Guitar: Ibanez RG370DX(stock)

Used to use an overdrive pedal so i didnt use
the ULTRA channel.
Some say its the amp and some say its my
guitar. Currently going to do some pots, 5
way switch and jack upgrades.

Any kind soul can help me? Or maybe its the
amp supposed to be that noisy on ULTRA channel?

HELP!

 

[CyanideJunkie]

Sounds like a faulty preamp tube.