[PROBLEM] Choppy Audio at HDMI

[IriDium]

Certainly does.

Looks like a lot of debugging is required.

I would.

1) Try a new flash of Xbian (With no addons or extras) - and try that - see if it is the same.
2) Unplug all cables that are not required except HDMI - try again.
3) Try a different configuration - RPi to TV, TV to AV.
4) Disregard AV - RPI directly to TV.
5) Check the Audio settings - remove all and add one at a time.
6) Check CEC settings
7) Throw the lot in the bin and buy a record player

Seriously, you need to eliminate all possible areas of problems, one by one.