1 JimmyR 4 weeks ago It's been a while since I had an amp with a spring reverb, so I'm still getting used the the reverb in my DRRI. I have managed to improve it a little (to my ears) - I have swapped out the two-spring tank for a 3-spring Accutronics of the same size I just happened to have and it sounds a lot better. I also swapped out the stock generic 12AT7 reverb driver for a NOS GE 12AY7 and it made a big difference - much smoother.But at anything above about 2 on the reverb level there is a buzz/hum sound related to the reverb I can't get rid of. Even if I turn the channel volume to zero it's still there. It only goes away with reducing the reverb level or switching off the reverb with the footswitch. It's annoying because now that I have some cool reverb I'd like to use it.I tried better RCA cables and they made no difference. Any ideas?Thanks!