Tough stuff that may indicate a problem for setter? (4,3)
I believe the answer is:
hard pad
'may indicate a problem for setter?' is the definition.
I know nothing about this answer so I cannot tell whether this works.
'tough stuff' is the wordplay.
'tough' becomes 'hard' (synonyms).
'stuff' becomes 'pad' (pad is a kind of stuff).
'hard'+'pad'='HARD PAD'
'that' acts as a link.
Can you help me to learn more?
(Other definitions for hard pad that I've seen before include "Distemper" , "Ailment of dogs' feet" .)