MOTM

I've had my 440 for a while, built it from a kit maybe a year ago, but haven't had a lot of time 
to mess with it besides some basic usage. Last night I was using the mixing part of it for the 
first time, and noticed an anomoly - the inputs are ring modulating each other. Two 
oscillators (300s), into inputs 1 and 2 (or any other combo), and twiddle the frequency knobs 
on the oscillators, and I get all kinds of extra sideband frequencies. Sounds just like a ring 
modulator. The exact same patch into my 480, and no problems, just the 2 frequencies, not 
interacting. Guess I've done something wrong - any ideas what?

Steve Drake