Usually a shock like that is due to excess RF on the chassis of the radio 
and from that to the microphone.
It sounds like you are getting allot of RF back down the coax.  Did you 
install a balun or make a coaxial choke at the antenna feed point?
If you are getting RF back down the shield of the coax, it'll cause RFI like 
crazy and cause the shock to happen.
Put a 1 to 1 current balun in at the antenna feed point, or make a common 
coaxial balun.  Just 6 or 7 wraps of the coax in a 4 or 5 inch wide coil 
making sure the coax never crosses itself.
This has to be done as close to the feedpoint as you can get it.
 All the radio and shack grounding in the world won't help eliminate RF 
coming back down your coax.
If you have a talking swr meter, check your reflected power.  It'll probably 
be very high.

73
Colin, V A6BKX
----- Original Message ----- 
From: "Tom Brennan" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, April 16, 2013 8:41 PM
Subject: Re: mfj 931


> I'm getting rf on all frequencies from 160m through 70cm although the 
> lower the
> frequency the more rf and the greater the on air him.  On frequencies 
> below 12m
> I do get a shock if I touch my mic which is metalic.
>
> Tom
>
>
> Tom Brennan  KD5VIJ, CCC-A/SLP
> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html