Paul,

Sorry for the delay in getting back to you. We hadn't forgotten you.

Had to pass this one off to one of our 9Z experts. With his many responsibilities, it took a few days to get an answer.

From your description, it sounds like there may be a missing "link" function in one of the mixers. Channel 7 sounds like it's not linking properly. Does it have "LIN" set?

Hope this helps.