Score for nine is accepted by Countdown host: UNWITTING (4,3,5)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

NONET (a piece of music written for nine players = a score for nine), then IS contained in (accepted by) HEWER (Nick Hewer, former host of the Channel 4 game show Countdown ). For the surface, part of the game involves making the longest possible valid word from a selection of nine letters.