[[email protected]]

Hi all,
I've read many topis the subject, but none seem to help in my case.

I have a Rockford fosgate amp hooked up to a factory head unit that i
want to keep. The amp turns on/off by itself quietly, but when I hook
up the head unit, it make several 'thumps' or 'pops' when turned on,
and also one wehen turned off.

I'm sure these are caused by the head unit, since when I disconnect it,
everything works fine. There are no other components used (eq's etc)

While trying to locate the problem, I also noticed somthing that could
be related - I get sound from the head unit by connecting the amp with
just one wire! To be specific, since I'm using speaker outputs from the
car cd player and high-level-inputs on the amp, I run (+) and (-) wires
for each channel. When testing, I disconnected all wires going from the
head unit to the amp. If I connect only one (doesn't matter which one)
I start to hear sound from that channel already... When I connect both,
the sound gets about twice as loud. How is this possible?
The head unit had 2 wires running to each of the original speakers, so
they weren't grounded to the chassis for sure. I replaced the speakers,
and made sure the're not shorted anywhere.

Now I'm thinking of using line level converter to transform the car cd
player output and use RCA jack on the amp... Will this help at all? Any
other thoughts how to get rid of the thump?