interference, not just on preamp outputs

[2rotor]

this whole problem is in my daily driver, which is kind of locash...
the other day i noticed my subwoofer was making a nice HUMMMMMM, and a pop when i press the brake pedal. obviously im picking up interference. nothing in my set up has changed, i have been playing this same combo for about a year or more with no problems.

i tried a different amp, new RCAs and a fresh ground wire on a new, clean spot of metal. the only thing i have left is that my head unit (pioneer) is being a bitch. ill try my OLD pioneer head unit and see if the problem carries on. I wanted to put my problem out there and get some other opinions while i was at it, though.

my door speakers (i only have 2 components in the whole system) are now also playing with some distortion, and my right side speaker is noticeably lower volume than the left.

yes my stereo is gay, and my equipment is not minty fresh, but its kind of a weird 'all of the sudden' problem.

any ideas?

[speedminded]

All the engine grounds properly connected? I'd check the head unit ground too.

[Member31410]

Read about a quick grounding fix on Pioneer head units here.

[2rotor]

as of this post, i havent read that link, but imagine its as follows:
reground the pre amp outputs.
which is what i did, i had to do this on the head unit in my rx7, but i think its a kenwood...
anyway, the sub problem is fixed now, i should have tried it to begin with, i was just too lazy. i think the right speaker is F'd partially, its still in and out, ill have it out and check the leads on it today, since the shop is hella slow...

thanks btw!

[2rotor]

wow, i just read that link, and the RCA grounding they did is overkill IMO, i just pulled the heat sink off the back and wedged a piece of clean copper wire between the RCA ground and the case.
to be more specific, the outer terminal of the RCA is linked between the two jacks, its covered by part or the head unit casing, so thats where i put the piece of wire, then i put the other end under the screw that holds the jacks in place.