My NAD 214 stereo amp is dead or dying. Any signal I run through it is
extremely distorted and I have to turn up the volume to even hear that.


Beginning a few months back it would sound fine and then all of a
sudden die and the sound would become horrible distorted. The time it
takes the amp to go from working fine to distortion box continually
shortens from 20 to 10 to 5 to 2 to 1 minutes. Now it doesn't work
for anytime at all.

I haven't been playing nice with it recently. I have run a microphone
and bass guitar through it. However, the amp had experienced the
problem I described above before this.

So my question is this: Is there any fundamental reason why running a
bass guitar or mic through this amp would hurt it? Also, does anyone
have any idea what might be wrong with my amp.

Thank you!
-Jon

Ps here is my setup in case it's helpful.
NAD 214 Stereo Amp
NAD 512 CD player
Adcom preamp
KEF Q55 speakers
Monster XP cables