A quiet laugh is awkward, having a problem with speech (7)
I believe the answer is:
aphasia
'a problem with speech' is the definition.
I can't tell whether this definition defines the answer.
'a quiet laugh is awkward having' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'laugh' becomes 'ha'.
'awkward' indicates anagramming the letters.
'having' becomes 'a' (I am not sure about this - if you are sure you should believe this answer much more).
'is' anagrammed gives 'si'.
'a'+'p'+'ha'+'si'+'a'='APHASIA'
Can you help me to learn more?
(Other definitions for aphasia that I've seen before include "Inability with language due to brain damage" , "Inability to use language, after a stroke say" , "disorder" , "Loss of ability to speak following brain damage" , "'Inability to use language, after a stroke perhaps (7)'" .)