Hi, I had the same sound from my speedo counter. Dealer advised me that they could not repair the counter but had to fit a new one, But doing this will reset the mileage to zero miles.
but then u could get it reprogramded!
I don't think the dealer would reprogramme the dials, I was told that the change would be logged in my service book and with the lexus data base. my clocks were changed @ 17,500 miles and new clocks have now done 4,200 miles, So i just add 17,500 miles to get correct mileage.