A while back, someone posted a video of a band composed of children, doing a cover of The Logical Song. Kids sounded great, but there were a couple odd things in the video.
Stumbled across this video of a guy talking about a previous video he had done, analyzing a Greystones performance. He took his analysis video down, because of the hate being directed at the kids, but, yes, his analysis showed that the audio of the performances is manipulated, to a degree.
Seems the band has responded to some of the feedback about their performances. This one, for instance, shows, in an inset, the kids doing the backing vocals that are added on to the performance.
Steve