[Yaesu] FT-100D, wild behavior randomly on PTT

[fire-eyes]

Hello List,

I am having a curious and aggravating problem. I have an FT-100D. On 2M 
(the only band I have an antenna for), i get an intermittent issue when 
I press PTT.

Sometimes it will transmit as expected. Other times, perhaps 30% of the 
time, it acts as if the PTT switch is dirty or bad. It then either fails 
to transmit, or does so in a very rapid on/off/on/off pattern. At the 
same time, it acts as if I am pushing either the up or down button on 
the top of the mic.

When this issue happens, it seems to be "down" that is somehow triggered 
more than up. Perhaps 80% of the time.

I have taken apart the MH-36b microphone. It looks okay in there, though 
I do not have any tools to do further testing. I was not able to get the 
board to separate from the mic body.

Could this be a hairline crack in the board, which is usually making 
contact fine but other times is not, which then somehow spits out 
incorrect signals to the radio?

I heard one idea from another ham, who mentioned that it could be RF 
getting back into the shack. However this problem happens just as 
randomly on 1W as it does at 50W. I have tried in FM and SSB, still 
seems the same.

It was also suggested that I try to key up the radio in another manner, 
such as a CW key, however I do not have one at this point. Nor the tools 
or much of anything to build one, as I've been out of the hobby for a 
number of years.

My match is good.

Does this all sound familiar to anybody?
-- 
"I've missed more than 9000 shots in my career. I've lost almost 300 
games. 26 times, I've been trusted to take the game winning shot and 
missed. I've failed over and over and over again in my life. And that is 
why I succeed." - Michael Jordan