Air conditioner clutch noise

it could be the clutch bearing is wearing out, which is not uncommon, but make sure it is the a/c clutch making the noise, because noises can be tricky, even though it goes away when you turn on the A/C. try spraying some WD-40 on the clutch pulley bearing area, that should change the noise a little and it won't hurt anything will evaporate in 3-4 minutes anyway, but you can hear if there is any difference, as there should be, when it is sprayed on the clutch.

I cleaned up the clutch today and got some increased clearance between the clutch face and the compressor, about .006". It seems to have eliminated the noise. I have had this noise for a couple of years. I did find a small piece of a serpentine belt in the clutch.