Noise and ringing on all channels. Preamp tube?

[eonblue]

Hey, I have a intermittent fuzzy/scratchy kind of sound which I can hear on all channels. Like, I said, it comes and goes and is louder dependent on the gain of the channel. Also, there is this really wierd high frequency ringing which comes and goes as well. How to proceed?

 

[Peter Diezel]

Please replace V1

 

[eonblue]

Thanks I'll give that a shot tonight.

 

[badgergman]

I had a similar experience with my Einstein a short time ago.

This fix cured the problem instantly.

In fact initially I just swapped V1 with V2 and vice versa and that cured it also. Now replaced V1 with a 12AX7AC5 HG+ and its solved.

Seems V1 works very hard?