Anyone else experiencing signal noise when ruing outboard gear via the ADAT ports into the Quantum interface?

I coect a Universal Audio 4-710d preamp unit to my Presonus Quantum interface via the ADAT optical ports. When I play my bass through the 4-710d there is signal noise in the form of pops and cracks. I have tried coecting the analog out from the 4-710d instead of the ADAT and it sounds fine. I also have run directly into the Quantum interface and have no issues. There is only noise introduced when I transfer through the ADAT ports.

Has anyone else experience signal noise issues when coecting outboard gear via the ADAT ports on the Quantum interface?

Thanks

Mike