Martin Clunes?
How did you get Martin Clunes to sing Gary Numan? I bet he wanted more than £60 for that voice gig.
Or was it Kipper? Actually, it sounded more like Kipper the Dog.
I could tell what the song was on the first hum. I tried it myself with "The Night" by the Four Seasons earlier in the week (which was an earworm for me, and I genuinely couldn't remember who it was by). Likewise Google: 0. Me: 1.