Play around as one fitting tobacco into pipe? (6)
I believe the answer is:
tamper
This clue is a double definition.
'play around' is the first definition.
(both can mean to mess or interfere with)
'one fitting tobacco into pipe?' is the second definition.
(tool used to prepare a tobacco pipe)
'as' is the link.
(Other definitions for tamper that I've seen before include "'Alter or falsify, documents perhaps (6)'" , "Interfere harmfully" , "Interfere (with something) without permission" , "Mess damagingly (with)" , "Meddle harmfully" .)