Faulty (5)
'faulty' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for unsound that I've seen before include "Faulty" , "Not strong or free from defect - perhaps evidence in court" , "Damaged" , "Ill-founded" , "Defective or flawed" .)
'faulty' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for amiss that I've seen before include "Wrong (a girl!)" , "Wrong; inaccurate" , "Faulty" , "Unsuitable" , "Out of order" .)