Noise in an old NAD 3020


I bought an old NAD 3020. It works great except, when I first turn it on I get distortion for about two minutes. After that I only hear the distortion when I turn a knob. Anyone know whats wrong here?
baileyje
The potentiometers are probably dirty and need to be sprayed and worked with some tuner spray. That is a common problem with those units.

As for the turn-on distortion, I used to have one that did that. It seemed to be exacerbated if I had the "loudness" switched in for some reason. But the amp sounds much better after it has been powered up for a while, so my suggestion would be just to leave it powered up all the time. It doesn't draw much power at idle, and that way it will always sound its best.
I just picked up a used NAD 3020B which seems to work fine. Unusual is that every time I powered it on, it seems to send a kinda of vrooom.... sound to my speakers for a second. I've sprayed the inside but still the same. Is this common with some units and what is the best DIY repair?
Hi:

My recently sold NAD 3020 use to "thump" when turned on and right after that one channel sounded like big sunami waves. Those noises usually disappeared in a couple of minutes.

The solutions were: Push mute button before powering on and let pass two or three minutes to get things warmed-up.

After that it should sound nice.

Good luck