Unfortunate instances, uninterrupted (9)
I believe the answer is:
incessant
'uninterrupted' is the definition.
(thesaurus)
'unfortunate instances' is the wordplay.
'unfortunate' is an anagram indicator.
'instances' with letters rearranged gives 'INCESSANT'.
(Other definitions for incessant that I've seen before include "Endless" , "Persistent" , "Ceaseless" , "Constant, unremitting" , "Without pausing" .)