Change bed again, causing some banter (8)
I believe the answer is:
badinage
'some banter' is the definition.
(badinage is a kind of banter)
'change bed again' is the wordplay.
'change' is an anagram indicator.
'bed'+'again'='bedagain'
'bedagain' is an anagram of 'BADINAGE'.
'causing' acts as a link.
(Other definitions for badinage that I've seen before include "Wordplay" , "Frivolous repartee" , "Drollery" , "Backchat, banter" , "Humorous, witty conversation" .)