Band's ending - is gig put off? (10)
I believe the answer is:
disconcert
'put off?' is the definition.
(putting off is a kind of disconcerting)
'band's ending is gig' is the wordplay.
'ending' suggests the final letters.
'gig' becomes 'concert'.
The final letter of 'band' is 'd'.
'd'+'is'+'concert'='DISCONCERT'
(Other definitions for disconcert that I've seen before include "Bother" , "Disturb, unsettle" , "upset" , "Shake up" , "Throw" .)