Strange problem with Omni ADAT input

Hey all. I've been using an all-Ligtpipe digital distribution system for years, with a rock-solid Z-sys Digital Detanger at the center, flawlessly moving audio between my RME Digiface, MOTU 2408 mkII and other devices. Just installed my Omni, and I get persistent crackling with any ADAT input routed through the Z-sys, while direct connection between any unit and the Omni works without problem. I can think of no logical explanation for why the Omni would see the signals any differently. Clocking is solid, with the Omni as master.



Has anybody else experienced issues with the Omni ADAT inputs? What am I missing here?