I'm guessing they are unbalanced can anyone confirm this?

Yes. It's a stereo 1/8" TRS minijack.

If you want balanced inputs, I recommend a juicedLink preamp and Magic Lantern...

http://www.dvinfo.net/forum/canon-eos-5d-mk-ii-hd/248970-5d-mark-ii-audio-exposed-series-complete.html

Thanks Jon, I have read that post. By turning down the audio almost all the way down and feeding it with my field mixer I am getting results equal to the JuicedLink and ML. If I did not already have the field mixer I would go in that direction.

ML can give you even cleaner results.

The analog gain in the Canon manual audio gain firmware is fixed at +31dB. All adjustments are made digitally in the Canon code. Magic Lantern lets you set analog and digital gains separately. I typically run +10dB or +17dB in analog and 0dB in digital. From memory, this reduced noise by another 12 or 18 dB compared to the Canon code. I'd have to look at my notebook to be sure...

This assumes that you can crank the gain cleanly out of your field mixer. If so (and if the unbalanced run from the mixer to the camera isn't so long that it picks up interference), you're golden!

Thanks, Jon not related however I picked up an AC hum probably from the cheap wall wart. :( Not from the unbalenced connection, everything is unpluged except the AC line.