[1000mp] MP in CW

[VE2FWW]

Hello 
I wonder if anybody using the MP in cw have noticed this....in CW...
When my MP turns to receive....I am hearing a noise like a clic in the speaker.....
It is not very loud, but during a contest ....it becomes annoying....
I have two FIELDS ...and I do not have this kind of noise when the come in RX after a transmission....
I would appreciate very much any input about this annoying sound comming from the speaker when the MP switches to RX.....
Many Thanks
NOEL