On 2/3/2009 2:25 PM Dave Platt spake thus:

The fact that it's a wind-like rumbling lends a bit of additional
evidence to the suspicion that it's in the RIAA stage, because this
stage boosts the lows. If it was just a white-noise source after the
RIAA stage it would sound more like a hiss than a rumble.

I had exactly this problem with a receiver years ago, and it turned out
to be a bad transistor somewhere in the preamp stages.

In my case, I was easily able to find the offending part by tapping on
the transistors, as the bad one had gone microphonic. You might try
this; turn the receiver on, turn the volume up just a little ways until
you can hear the noise (not too high, now), then tap on all the
transistors you can see in the preamp section (near the input
connectors, probably). If you hear a big "thump!" when you hit one, it
needs to be replaced.

In the case of my receiver, I was able to get a NTE replacement that was
close enough. The thing still works fine 15 years later.


--
Personally, I like Vista, but I probably won't use it. I like it
because it generates considerable business for me in consulting and
upgrades. As long as there is hardware and software out there that
doesn't work, I stay in business. Incidentally, my company motto is
"If this stuff worked, you wouldn't need me".

- lifted from sci.electronics.repair