There are two minor issues with the MT S/PDIF connector:
<1> If one connects an external power source to the USB plug, there sometimes isn't room to accommodate the outer casing of both the S/PDIF connector and USB plug. In this instance, finding connectors with smaller casings, or simply shaving down the outer casing on one or both of the connectors, will resolve the problem.
<2> The MT has a narrow / thin "ring slot" into which the outer ring of the male RCA inserts. Some RCA-male connectors have a ring that is simply too wide to fit into the ring slot. Unless one hacks the MT ring slot (ugly and potentially damaging) or the RCA-male ring itself (how one might thin down the ring, I haven't the foggiest idea), no amount of tweaking will fix the problem. The only real solution is to find a S/PDIF cable that uses a thinnish ring on the RCA-male connector.