Distributor Noise

[nassaupmf]

I have a 31 Deluxe roadster. After starting, the distributor emits a high pitched sound which increases as the RPM does. I have gone through 2 rotor caps in a couple of months, as the the gold pice on top snaps off. I also have a 30 sedan, and have taken both the rotor and distributor cap off of it and put it into the 31 with the same result. The cam is lubricated.

Any ideas?