Something wrong with a knot? (5)
I believe the answer is:
hitch
'a knot?' is the definition.
(I know that hitch is a type of knot)
'something wrong' is the wordplay.
I cannot quite see how this works, but
'something' could be 'it' (both can refer to an object) and 'it' is found in the answer.
This explanation may well be incorrect...
'with' acts as a link.
Can you help me to learn more?
(Other definitions for hitch that I've seen before include "Yank" , "To travel without paying" , "unite" , "Temporary difficulty" , "Make fast" .)