Microphone goes "quiet"

[jokerl90]

I have an intermittent problem, when keying up sometimes and while talking sometimes the mic will get "quiet" . I can hear the difference through talkback, the radio's needle will swing and the transmit light will still light up, and someone close can still hear me on their radio, but the sound volume is very low.
I have 3 Turner RK56's and one stock cobra mic that this is happening with. At first I thought it was was the radio, but I have 3 Cobra 29's and they work ok with other mic's. This happened with 1 cobra 29 new out of the box in less than 5 minutes. I'm sure it's a mic problem as all radio's work fine with another stock Cobra mic I have.
I have cleaned the PTT switches and don't see any loose connections at either end of the cord. Could it be that one of the wires is loose or damaged that could cause this, allowing it to work at a reduced volume?
Any ideas? Thanks in advance!

 

[Robb]

I would check your coax/antenna first.
Then see if the radio is getting the proper voltage - next.
~13.5v; +/-.5v

If it is happening with three different mics on the same radio; then I would suspect something is wrong with that radio. See above...

 

[jokerl90]

Thanks for the reply!
I have 3 Turner RK56's and one stock cobra mic that this is happening with. At first I thought it was was the radio, but I have 3 Cobra 29's and they work ok with other mic's. This happened with 1 cobra 29 new out of the box in less than 5 minutes when using the above mic's. I'm sure it's a mic problem as all radio's work fine with another stock Cobra mic I have.