Some deficiency apparently in tune quality (7)

I believe the answer is:

unequal

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'some deficiency apparently' is the definition.
I can't judge whether this definition defines the answer.

'in tune quality' is the wordplay.
'in' indicates the answer is hidden within the clue.
'UNEQUAL' is hidden in the letters of 'tune quality'.

Can you help me to learn more?

(Other definitions for unequal that I've seen before include "More or less" , "at different levels" , "Not evenly balanced" , "Not identical" , "Varying" .)

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

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