Schitt freya preamp hum- how do I get rid of this?

It could be a bad tube, that preamp should be very quiet. 

If you consider that you have a faulty product, the best thing to do is to let the company know and they will do what good American companies always do.

They actually want to know if they are shipping defective products so they can fix any quality control issue so it will never happen again.

And hear about what may have been an innocent mistake first-hand rather than reading all about it in the forums.

A competitor with ill-intent may characterize the Freya as being "cheap" and therefore inherently faulty.   Ouch.

If you consider that you have a faulty product, the best thing to do is to let the company know and they will do what good American companies always do.

I agree!

Is the hum through the speakers, if so, both speakers?  If it is through the speakers, but only one speaker, try changing the tubes from left to right.  If the hum changes speakers, you know it is a bad tube.   If the hum doesn't change speakers may be a bad unit.  But one last test, gently tap the tubes, and if you get a loud pop it may just be microphonic tubes.   

The above testing should just take a couple of minutes.  If it doesn't help, be sure to send it in for a replacement.