Talkative type has volume trouble on vacation (7)
I believe the answer is:
'talkative' is the definition.
(similar in meaning)
'type has volume trouble on vacation' is the wordplay.
I cannot quite understand how this works, but
'volume' could be 'vol' and 'vol' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for voluble that I've seen before include "Gabby, garrulous" , "Incessantly speaking" , "Given to talking a lot" , "Loquacious" , "With plenty to say" .)