Robert,
A quick question for you, did the delay stay with the video you were sourcing the audio from? The reason I ask, is that I had a similar situation using 9 streams of ProRes422 and tapped two units for audio, the delay followed the two units that I was sourcing the audio from. All 9 streams had the same audio file. It became apparent after moving the audio jacks around, that the delay was a result of Win 7/CPU playing the audio. My solution (being as I had 18 machines 9 prime and 9 backup) was to jack all of them to get the delay into all the units. I could move the jacks (prior to jacking all of them) and watch the delay follow on the display machines. Still working on narrowing down the true reason (driver or hardware issue) but checking to see if you had experienced the same issue.
Thanks in advance
Goldie