Unwisely rely on ancient music maker (4)
I believe the answer is:
lyre
'music maker' is the definition.
(lyre is a kind of musical instrument)
'unwisely rely on ancient' is the wordplay.
'rely' can be anagrammed to 'LYRE'.
However, I'm not sure how the anagram is indicated.
Can you help me to learn more?
(Other definitions for lyre that I've seen before include "Music-maker" , "Old instrument, like a harp" , "Ancient stringed musical instrument with U-shaped frame" , "Ancient harp-like instrument" , "Old stringed instrument" .)