DAC has a lot of offset

[Beowulff]

Has anyone else experienced this?
Both DAC channels have between 4 and 10mV of offset when they are supposed to be at zero volts.

This is a problem for me, since I really need the output to go to zero when it is supposed to.

[Beowulff]

I wasn't able to find any suggestions on how to fix this, so I added a small positive bias voltage to the non-inverting input of my Op Amp signal conditioner. This fixed the problem, but at the expense of a new board revision, and some reduced dynamic range (zero volts out now starts at a DAC count of 20 or so).