2006 Chevrolet Silverado Voltage Issues

Voltage fluctuates at idle sometimes

Hi scotty,

as in the video, sometimes when idling my Silverado voltage gauge is all over the place. It doesn't seem to do it while driving. I also know its not the gauge, as I have checked with a multi meter. Also, sometimes my radio randomly cuts out. It has happened 3 times now, and once I could trigger it by turining on the high beams. Today I went out and put a full load on the alternator and checked all voltages with a meter and everything checked out okay. Is the alternator slowly on its way out? What could be causing this? Also I should mention in the times the radio has cut out, the lights all dim, and the voltage gauge dips way down.

either alternator is going out, or the wiring from the battery to the alternator to the gauge is shorting out