Hey everyone. I'd like some help diagnosing a hum (sounds more like white noise) coming from the right channel of my CA 800. I didn't notice it when I purchased it months ago because when the amp is cold it isn't audible. Hoping there's an easy enough fix for it. Here's what I know: -isn't audible for the first couple of minutes after power up -right channel only -noise drops slightly when I switch the audio muting to -20db -noise gets way louder when I switch off the preamp coupler on the back -no other switches or knobs change the noise -I'm always running it in class A, but the noise is still there in class B Really appreciate any advice on this. This amp sounds fantastic, otherwise. Thanks!