If the parts u have Are usable, they can have someone getting the wiring back on point. But Factory wires dont usually just "go bad". Most likely the speaker is simply going bad, and the Aux Jack, IF that is a part of the Factory Radio it most likely Can Not be repaired. Cost wise you will be better off replacing IF these turn out to be the case. Good luck!
You probably need more than a rewire but they can definitely help you with the problem
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