The programme's producers will vet content ahead of broadcast and choose the best clips to screen around the music video playlist.
This is the next step in viewer interaction for the title, which until now has been limited to on-screen text messages and selection of music videos.
Flashbox will screen daily from 4pm to 5pm from 19 March. Emap is promoting the launch across its music TV stations including Kiss TV, The Hits, Magic TV, Kerrang! TV, FHM Music TV and The Box.