Complaint affecting consumer goods — opinion broadcast loudly at first (4,9)
I believe the answer is:
food poisoning
'complaint' is the definition.
(food poisoning is a kind of health problem)
'goods opinion broadcast loudly at first' is the wordplay.
'broadcast' indicates an anagram (letters scattered or cast around).
'loudly' becomes 'f' (short for forte - 'loud' in music).
'at first' says to put letters next to each other.
'goods'+'opinion'='goodsopinion'
'goodsopinion' anagrammed gives 'oodpoisoning'.
'oodpoisoning' put after 'f' is 'FOOD POISONING'.
'affecting consumer' acts as a 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 food poisoning that I've seen before include "Salmonella, etc." , "Botulism, for instance" , "Acute illness caused by contaminated edibles" .)