As performed by Viva Vox in May 2011. The arrangement is by Boris Balunović, and it is conducted by Jasmina Lorin. Ivan Propadović is the soloist. [via r/videos]
Heather says it sounds vaguely like something from Spongebob Squarepants.
Here's the original:
https://www.youtube.com/watch?v=KzGKsXPBILw