A run of notes getting higher or lower (7)
I believe the answer is:
deflate
'lower' is the definition.
(thesaurus)
'a run of notes getting' is the wordplay.
'a run of' becomes 'eflat' (I can't justify this - if you can you should give a lot more credence to this answer).
'notes' becomes 'de' (two musical notes).
'getting' is an insertion indicator.
'eflat' placed within 'de' is 'DEFLATE'.
'higher or' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for deflate that I've seen before include "Release gas from" , "Puncture, collapse like balloon" , "Take air" , "Release air from" , "Let air out of, like balloon" .)