Your problem is not that of a bad ground as much as it is a "ground loop"
Radio Shack sells ground loop isolators.  They replace or install inline to
your amplifier inputs.  I have these on my set up and work perfectly.

Dennis

-----Original Message-----
From:   Vanagon mailing list  On Behalf Of Chris Pittack
Sent:   Wednesday, August 27, 1997 3:35 PM
To:     Vanagon@GERRY.SDSC.EDU
Subject:        Stereo Wiring

Hello Collective,

I have a question regarding the wiring of my stereo.  I recently
installed an after market Sony CD Head Unit, Boston Acoustic 4"
speakers, Sub-Woofer and an Amplifier.  Wired everything up and it
sounded great for a month.  The other day one of the speakers started
buzzing!  Pulled the speaker and exchanged it for a new one.  New
speaker also buzzed.

Checked the connections at the amplifier and visually everything seemed
fine.    There are two coax cables that come from the head unit.  Cable
A (Left Front Amp In) and Cable B (Right Front Amp In).  If I unplug
Cable A, LF speaker stops working and RF speaker plays beautifully.  If
unplug Cable B, RF speaker plays and LF speaker plays and it buzzes.

If I take Cable A and plug it into the RF Amp In, RF speaker plays
beautifully.  So I deduce that the signal reaching the Amp is OK....am I
correct?  The fact that both RF and LF play when only one signal is
being sent to LF Amp In leads me to believe there is a bad ground?  Am I
close?  I tried grounding the Amp body but nothing happened!  What could
cause this?

I am a Financial Analyst, are there any electrical engineering types out
there that could help me?  If my reasoning is sound I'll just return the
Amp and tell them about the ground leak.  However, I don't want to be
laughed out of Magnolia Hi-Fi when I bring in my Amp.

Thanks in Advance of any Advice!

Chris P.   Seattle, WA
'89 Oil Burning Jetta "Jake"
'87 Wasserboxer GL "Lewis"
'82 Oil Burning L "Billie Rae"