Might be the monitor you are viewing or it could be the settings on the camera. Here are some stills from my camera and they don't exhibit any noise problems. I could make noise if I want. Often, if you are viewing on an LCD monitor you will see all sorts of noise in the blacks which is not the camera but the monitor.
http://www.bluesky-web.com/hdv.htmWalter Graff
BlueSky Media, Inc.
walter@bluesky-web.com
http://www.bluesky-web.com
Offices in NYC and Amherst Mass.