Channel loss Windstar stereo

My 2001 Windstar stereo suddenly lost all of the Right channel speakers.  I did the extreme and replaced the stereo.  The replacement stereo did not solve the problem.  I really doubt both stereos have the same problem.  Any ideas on where I can go next?

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Captain NP :errr:

If you replaced the deck and used the proper wiring harness, then you have proven that the trouble is in the wiring to the speakers.  Open up one of the right speaker locations, wire a temporary speaker wire to the speaker and to the deck, test it.  But just to be on the safe side (for the deck's sake), also temporarily disconnect the original wires from the speaker, and of course, from the deck.  If you get sound, run new wiring from the deck harness to the right speakers.  May as well replace those factory originals while you're at it.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Some additional information for those of you that might be better at troubleshooting based on symptoms.  When the stereo is on then the ignition is turned off along with the door open (this action actually turns off the stereo), after about 3 seconds a pop sound is heard in the right speakers.  This pop also happens after I plug the wiring harness in while I am sliding the radio into its dash location.

Stevdart----good suggestion.  I'll give that a try.

Anybody think that continuity checks of the wires would be a good idea also?

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Captain NP