Herbert MK1 ch3 squeals

[6string_highway]

Hi,
Had a diezel Herbert mk1. Both Ch1 and ch2 are just fine. Its just when I use ch3 having its gain past 12:00 where the squeals occurs below that its just fine. Even with no guitar plugged it squeals, I am suspecting its a capacitor issue. Has anyone experience the same as mine.

 

[Smash]

Til someone answers that knows, i would change out preamp tube in v2 and see if that fixes it

 

[Smash]

 

[6string_highway]

I'll try replacing the v2 pre amp tomorrow. Hopefully it will fix though I doubt that this is a tube pre issue, had some tube microphonic issue with my roadster and JVM before and this diezel issue is diff. Since ch2 is working and ch3 with gain below 12:00 is working as well. And no popping sound or fry sounding that associates a microphonic tube.

 

[Smash]

I'll try replacing the v2 pre amp tomorrow. Hopefully it will fix though I doubt that this is a tube pre issue, had some tube microphonic issue with my roadster and JVM before and this diezel issue is diff. Since ch2 is working and ch3 with gain below 12:00 is working as well. And no popping sound or fry sounding that associates a microphonic tube.

I hope it is a tube. Such a simple fix

 

[6string_highway]

Replaced the v1 and v2 preamp tube and still got the squealing issue. hopefully the capacitor change this weekend will solve this annoying issue.