I'm thinking of buying a Fireface UCX to add to a Digiface + Prism Orpheus setup (+Mac Mini).

I bought the Digiface to improve the latency of the Orpheus, but only saw a 2 ms improvement, down from around 11 ms using the Orpheus firewire driver.  Prism have since confirmed that they are using the internal firewire busses to route ADAT data when the Orpheus is in stand-alone ADAT mode.

They have also confirmed that the added round-trip latency (non AD-DA) of this ADAT path is around 4 ms!  I was shocked to hear this.

Having spent this much money only to find out that the Orpheus is using such high internal buffering just for ADAT streams I'm a little wary about buying a new interface without seeing a significant reduction in ADAT buffering/latency.

With the UCX in stand-alone mode, can someone tell me how many samples of round-trip latency I can expect (not including AD-DA conversion) to incur inside the UCX.  Will it be less than 1ms (and definitely below 4ms!).

Knowing RME, I think I know the answer, it's just that after having spent so much money I don't want to waste any more.

Danno