Outputting 5.1 sound from mkv’s via optical to an A/V receiver

hardware
I'm still yet to master the black art of outputing 5.1 sound from mkvs in Media Center to my A/V Receiver. At least now I've recorded how I got it working this time.

OCZ vertex 3 vs OCZ vertex 2 vs WD Black Sata 3

hardware
What will win? OCZ's latest performance SSD? OCZ's previous gen performance SSD? Or Western Digitals 'performance' HDD? I've got the answer here, inside my new box!