Convertible Vehicles - Noisy Blower Motor

Has anyone experienced a very noisy blower motor? I just bought a 2000 Firebird v6 convertible. The blower is making a very load vibration type of noise. The people I bought it from have a 1999 WS6 convertible and it makes the same noise. Is this normal? I don't remember my 95 formula convertible sounding like this.
Mark

Take it out and look at it first. Quite often something gets caught in the squirrel cage and makes noise.

look here http://www.v6f-body.com/showthread.php?t=2220&highlight=blower