Found fault with new red cap (6)
I believe the answer is:
carped
'found fault' is the definition.
The definition and answer can be both to do with communicating as well as being past participle verbs.
Perhaps there's a link between them I don't understand?
'new red cap' is the wordplay.
'new' indicates an anagram.
'red'+'cap'='redcap'
'redcap' is an anagram of 'CARPED'.
'with' is the link.
Can you help me to learn more?
(Other definitions for carped that I've seen before include "Complained like goldfish?" , "Raised petty objections like goldfish" , "Raised trivial objections" .)