Strange; does this deck have an integrated amp built in?
If so I would disconnect everything but maybe one speaker and the two power wires and ground and see if you can narrow down what is causing it.
On my deck I ran the power from the power distribution block and the ground to the passenger side strut tower point.
If so I would disconnect everything but maybe one speaker and the two power wires and ground and see if you can narrow down what is causing it.
On my deck I ran the power from the power distribution block and the ground to the passenger side strut tower point.
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