I did some more poking around ... caused me to go get my outlet tester and plug it in..... and it indicated no ground! Moved it to another outlet and it works just fine.
You should not be relying on the the mains ground to provide signal integrity.
Hmmm, I am not sure I understand this completely. The ground lead on the probe was connected to common on the power supply. Are you saying that I need another ground?
I believe (could be wrong) that the green terminal on the power supply is a mains ground. The actual power supply outputs are AFIK floating/isolated from the mains ground. So, yes, you do need to add a ground to the power supply output.
I had originally assumed that you were using the mains ground(s) as your common/system ground.
Edit: May be talking at cross purposes here. Can you clarify what you are calling ground and common, and where these are connected on the power supply?