In the early 2010s, I used to watch international music videos on a channel called MYX.
The song I am looking for features a boy band who gets sucked into the past to a TV set from the 1960s. While in the past their life sort of parallels the Beatles. A bunch of kids watch them on TV with one kid pretending to sing into a hairbrush and another using a hairbrush as a guitar. The music video ends with them getting back to the present. I think there might have been a part with them running away from crazy fangirls but I am not sure.