Out of curiousity... Do you actually pronounce the "r" in "arse" over there, or is it silent?
In order words, do you say "are-ss" or "ass" or "ahh-ss?"
I haven't been paying enough attention to tell where Linguo is from, but hereabouts, it's a hard r: "ahrss". In most of England it's pretty much the same, but with a slightly softer 'r'. Some regional English accents may miss out the 'r' altogether and pronounce it more like "oss".
Australia...well, that's anyone's guess, isn't it?