PCV Valve 'buzzing'

Should my PCV valve be 'buzzing'? The check ball that's in it seems to vibrate back and forth and it appears to be causing a bit of a vacuum leak. When I manually plug the valve my o2 meter drops down almost a whole point richer, when I let it loose it jumps back up.

I read there are different PCV valves for different vacuum rates of an engine. How do you determine which one to use and what is the correct behavior of the valve?