I'm connecting my Multiface to a Behringer Ultramatch Pro SRC2496 A/D/A converter using the S/PDIF connectors of the Multiface and the RCA connectors of the SRC2496. Just like the Multiface, the SRC2496 can send/receive an AES/EBU signal over its RCA connectors (even though it also has dedicated XLR AES/EBU connectors).

My question is this: what's the difference between running the Multiface in AES/EBU mode ("Professional" box is ticked in the control panel) vs. S/PDIF mode ("Professional" box is un-ticked)? Is the quality any better, or are there any other advantages that AES/EBU has over S/PDIF? Is  the clocking any better for one vs. the other? I'm curious, because according to the SRC2496 manual, it must be clocked to its digital input if using it as a D/A, even though there's a BNC Word Clock In connector (which only works if you're using it as an A/D converter for some reason).

Finally, if I use the Multiface in AES/EBU mode, can I still use a regular S/PDIF cable (RG59 75-ohm with RCA connectors)? Or should I be using a different type of cable? i.e., is there such a thing as an AES/EBU cable with RCA connectors?