Analog RYTM humming

I just purchased a new Analog RYTM and it has a faint low-pitched hum (at all times), which becomes very loud when I touch the metal enclosure. (Slightly louder if I touch the face; significantly louder if I touch any of the sides).

I am currently monitoring it over USB through an Overhub and then into my iMac, then out to a Universal Audio Apollo Twin which has the headphones plugged into it.

I will of course try hooking audio cables up to the Apollo Twin and see if the humming is also present with that input setup.

But I wanted to check and see if anyone has had this issue or has any ideas what could be up?

The RYTM is plugged into a pretty good power strip (but not a power conditioner). I haven’t had any problems with any other gear humming like this when running through that power strip.

Thanks for any ideas…

Perhaps something like this: http://forum.cockos.com/showthread.php?t=113721