Differences in pitch offering breaks in play (9)
I believe the answer is:
intervals
This clue is a double definition.
'differences in pitch' is the first definition.
(as in musical intervals)
'breaks in play' is the second definition.
(as in theatrical intervals)
'offering' acts as a link.
(Other definitions for intervals that I've seen before include "Times between acts" , "Net's viral (anag.)" , "Intermissions" , "Periods of time between parts of a play" , "Rests" .)