Somehow aware, though confronting unknown impediment to hearing? (6)
I believe the answer is:
earwax
'impediment to hearing?' is the definition.
'somehow aware though confronting unknown' is the wordplay.
I cannot really understand how this works, but
an anagram of 'aware' is 'earwa' which is located in the answer.
'unknown' could be 'x' (algebra) and 'x' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for earwax that I've seen before include "Potentially deafening build-up" , "Otic deposit" , "Hearing problem" , "Shell-like secretion" , "Soft yellow substance secreted by glands of a certain organ" .)