VHF/UHF Purgatory Continues

The Kenwood Service Center called today regarding my TM-D710a.  They say they can’t find anything wrong and want me to send them the microphone.  So I packed up the mic and power cord and shipped it off.

This is puzzling.

I know it is not antenna related because I’ve checked the radio using two different antennas each with a different feedline.

I know it’s not the power supply (Astron RS-20A) because I continue to operate my TS-520 on it with no problems.

I suppose it could be the power cable.

Oh well.  Time will tell.