One is unusually sound (5)

I believe the answer is:

noise

'sound' is the definition.
(a noise is a sound)

'one is unusually' is the wordplay.
'unusually' indicates anagramming the letters.
'one'+'is'='oneis'
'oneis' with letters rearranged gives 'NOISE'.

(Other definitions for noise that I've seen before include "interference" , "Fuss" , "Confused sounds" , "Loud or disturbing sound" , "Unwelcome sound" .)

I've seen this clue in The Globe and Mail and The Times.

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