SSB pinning meter

Cobra 148 nwst, I have two giving me problems, first cb pins the meter, second cb meter bounced quickly in the 1-3 range, yet when I speak I get full gain, antenna is good or not shorted, tested a couple other cb's with same antenna and mikes, they operate normal. Anywhere I should start looking first?

Also when I touch the mike cord or case the radio seems to get a slight better signal, as in volume goes up a little.

Thanks