[TenTec] NO AUDIO in transmit OMNI VI

[John King]

Hello Ten Tec lovers and users !!: 
I have a "beloved" Omni VI plus that I have owned about 25 years and that will always be my favorite radio. I have  newer radios and Ithe OMNI VI has been setting idle for several months. When I put it back into service, it worked as it should, EXCEPT for audio getting from the microphone to the audio/TX board. I have checked the plug in connectors on that board.
The PTT works as it should and the radio is pumping out RF from the finals in the tune position. The receive is working well !!
The lack of audio getting to the VOX circuitry and the audio/transmit board prevents the Omni VI from working to transmit USB and LSB. Two microphones have been tried and neither makes a difference. I have the manual and the pictures of the boards and their locations. I have removed the plugs and re-seated them in the event that there was a loose one or some that were not properly properly seated or had some slight corrosion.   

I am an OLD dude and can use some help in running this problem down. I know that there are some really knowledgeable OMNI VI owners and I communicated with one in North or South Carolina via email about a year ago before the problem reared its' ugly head.
If any of you have experienced this problem or have knowledge that might help me find and cure this problem, I will greatly appreciate your input. Please assist me if you can.
Thanks and 73,John, K5PGW ( licensed 1958)