I'm happy the language selection works for someone

Yes, I've noticed there is a problem with lagginess. This is partially to do with the lagginess of ovi maps itself. I find I need to overlock to 1ghz for it to keep up. With even more logic in javascript for the voice logic it struggles.

I have a couple of improvements to look at. One is in the way a play the sounds: I create a new audio element for each sound each time it is played and then remove it. It might be possible to precreate the elements and use the play method, though microb's audio support seems a bit buggy.
Another possible improvement is to "predict" the position a bit in advance, but this has a lot of potential for error.