Quiet about pronunciation tip (10)
I believe the answer is:
prediction
'tip' is the definition.
(thesaurus)
'quiet about pronunciation' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'about' becomes 're' ('re' means regarding or about).
'pronunciation' becomes 'diction' (diction is a kind of pronunciation).
'p'+'re'+'diction'='PREDICTION'
(Other definitions for prediction that I've seen before include "Forecast" , "Prophesy" .)