Adding Axe-FX III to composite device (Mac) kills output

[plyall]

Folks -

I have been chasing clocking problems around my newly rebuilt studio for the past few days.

I have two separate word clock masters (only one in use at a time).

What I find is that if I add the Axe FX III to the aggregate device, I typically lose all audio. Here's a picture of my aggregate:

 

[plyall]

To add to this, AXE III is getting WC sync from the Fireface. Apollo is getting WC sync from the ADAT out of the Fireface. All at 48 Khz.