Problems retreat before beginning to subside (9)
I believe the answer is:
drawbacks
'problems retreat before beginning to subside' is the definition.
I can't judge whether this defines the answer.
'problems retreat before beginning to subside' is the wordplay.
'problems' becomes 'draw' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'retreat' becomes 'back' (to retreat is to go back).
'before' is a charade indicator (letters next to each other).
'beginning to' says to take the initial letters.
The first letter of 'subside' is 's'.
'draw'+'back'+'s'='DRAWBACKS'
Can you help me to learn more?
(Other definitions for drawbacks that I've seen before include "Disadvantages, hindrances" , "difficulties" , "Snags" .)