For years I've been a fan of the song from their second album, Ágætis byrjun. When I look for the English translation, everything is translated, except for the "chorus":
I'm back
Inside of you
It's so nice to be here
It's just a quick stop
I fly around in underwater
On hotel connected to Electrical Tables and feeds
tju tju
But what is tju
? Google Translate just gives me the same word back. I assume it's a vocalisation, like "Ooooh", or maybe a "yeaaah", but it could be an Icelandic term, like "oi" is to some English speakers (Australia, Britain etc.)
Any clues?