Casio CZ/ VZ/ FZ - Pro Series

OK,
So I recently bought a VZ10m. Compared to my other sound modules and 
synths, this thing is noisy! By that I mean it puts out a pretty 
significant amount of white noise on its output signal. I have to turn 
down the gain on my mixer to nearly 50% before I get it to be just 
inaudible. But then, I lose a great deal of volume dynamics. Many of 
the more subtle patches are too quiet.

I did some searching on the web and found a reference from 1990 saying 
that these units were known to be noisy. What I would like to know 
from folks here is if this is really a common trait or whetther it 
looks like I've got a box with some output amp problems.

So, could someone out there tell me, if you crank up the gain on your 
box' line level outs, do you get the noise also? If so, then I would 
suspect that this is just a common trait of these synths.

Thanks