Perhaps less a ferry question and more a question for music buffs, but nevertheless I've tracked it down.
The catchy tune in the recent DFDS adverts is called Something New and is sung by Mads Langer.
The song was performed by the Danish singer on-board Crown Seaways and the video can be seen below:
If you've missed the adverts then here's one of the most recent:
I'm a huge fan of this catchy tune. It was written purposefully for the DFDS radio and TV commercials and the lyrics are really nice. It makes me want to sail away right now...
Fancy sailing away? Sail away with DFDS here °.