If I remember right... I think this is from the first episode of the first season? Where they're watching that rock concert DVD and Ritsu is telling Mio they should form a band.
Pencilsoot said: Something about Mio looks different. I can't put my finger on it though...
Probably because, if nr22 is right about what episode is from, Mio is probably at least a year or two younger than she was at the actual start of the series, as it would have been a flashback.