Grab another set of RCAs, run them over the top of the seat, install the headunit, see of that fixes your problem. If it does, you have bad cables, if it doesnt, you have an issue with the jacks in your headunit.
Just a silly thing, are your amps still on whenever this happens? I was wondering if your remote turn on connection is possibly making/breaking connection. Kinda strange for all 4 (I am assuming 4) RCAs to quit at once. Just food for thought. Hope this helps...
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