The US star, who has been jetting around the globe in-between filming for the series, even left the building shaking this week with the bass from his sound system.
"Will.i.am goes everywhere with his music kit so he can lay down tracks wherever he is," a source told The Sun. "So it was no surprise to everyone when he and his crew turned up with a stack of gear on the first day.
"Producers thought it was great as we want him to be happy as Larry while he's on the show, and who knows what ideas he'll come up with for his acts?"
However it seems not everyone based at the BBC's TV Centre in West London was happy with their new neighbour.
The source went on: "The stuffy suits upstairs were a bit unhappy about it. Will has some serious bass in there and it was vibrating the walls — you could almost see the dandruff being shaken off their heads."
The Voice UK will kick off on Saturday night on BBC One, and after months of hype and millions of pounds spent on production and the coaches, it'll be a tense time the day after when ratings come in.