Audio Systems: stereo cutting in and out, antenna center, antenna connections

Question
My son installed a Panasonic Model# CQ C1335U 50x4 and 4 new TSA6871R 3 way 240 watt Pioneer speakers. The problem is it sounds like the radio is switching from stereo to mono constantly- Cd's sound fine. All wiring looks correct and antenna is hooked up. Alternator at 14 volts is unit bad? Thanks Glen

Answer
Better check the antenna connections and cable - especially the ground.  How about AM radio? Is it okey?  

Here is a simple check:  Remove the antenna connection at the rear of the Panasonic; take a 10 to 15' of single insulated wire and with one end stripped of insulation about 1/2 inch insert it into the antenna center connection.  This temporary  antenna should bring in the strong, local stations clearly.  If this works well then the antenna is the problem.  If it still has the switching problem you may have to exchange the Panasonic unit.

Hope this helps.

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