The following is a true story.. I should know.. It was my hair that was being torn out by the owner it happened to (ME).
Dash Radio (A Pioneer, not that it matters) on my Damon..When new it worked great for CD's and other line-in sources (Crap as a radio but that is not it's fault) but after a few years suddenly the audio would cut out and in and out and in..Was driving me mad.. Though it was loosing power due to a bad wire..Bypassed wire..NO JOY (Well improved for a bit but...) kept tearing out hair,, Traced the problem (By wiggiling wires) to the neighborhood of a high power audio amp near the parking break pedal.. But still no joy.. I mean it HAD to be a bad connection.
Next to the side wall mounted Amp, on the firewall, is a multi-pole relay.
Lots of RCA type (phono) cables going to them.. All well connected.
Finally noticed that the big speaker wires from the amp did NOT go to the RCA's as I thought they would..... They went to a MOLEX plug.
Pressed,, heard a SNAP as the latches hit home and latched
AND... let my hair grow back in cause that problem was HISTORY!!!
There is a suggestion or two embedded in that story.
Home is where I park it!