External clocking issues with Apollo and HEDD 192 help!

Hello,

I just purchased a UAD Apollo Quad unit to be my new audio interface with Cubase 6. When the Apollo is set to use it’s own internal clock, it works fine in Cubase. But when I hook up my Crane Song HEDD 192 converter to it (via SPDIF) and then set the Apollo to external clock and run the HEDDs clock as the master, the audio coming out is out of time and distorting heavily.

I contacted Crane Song tech support and they said it is an issue with my DAW configuration. In the Cubase Device Setup the Apollo interface is selected. I didn’t see an option to select an external wordclock in Cubase.

Can someone please help! Thanks!