Soft rock featuring in metal concert (4)
I believe the answer is:
talc
'soft rock' is the definition.
(I've seen this in another clue)
'in metal concert' is the wordplay.
'in' indicates a hidden word.
'TALC' can be found hidden inside 'metal concert'.
'featuring' is the link.
(Other definitions for talc that I've seen before include "(Mineral providing) powder" , "Baby powder" , "It is used to absorb moisture" , "Cosmetic powder" , "Bathroom dusting powder" .)