Rogue broadcast not up to scratch (8)

I believe the answer is:

impaired

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'not up to scratch' is the definition.
I can't judge whether this definition defines the answer.

'rogue broadcast' is the wordplay.
'rogue' becomes 'imp'.
'broadcast' becomes 'aired' ('aired' can be a synonym of 'broadcast').
'imp'+'aired'='IMPAIRED'

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(Other definitions for impaired that I've seen before include "Faulty" , "Had negative impact" , "Disabled" , "Damaged, marred" , "Spoilt" .)

I've seen this clue in The Telegraph.

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