You are speaking softly but critically (8)
I believe the answer is:
urgently
'critically' is the definition.
Both the definition and answer are adverbs. Perhaps there's a link between them I don't understand?
'you are speaking softly' is the wordplay.
'you' becomes 'u' (I've seen this in other clues).
'speaking' indicates a 'sounds like' (homophone) clue.
'softly' becomes 'gently' (synonyms).
'are' sounds like 'r'.
'u'+'r'+'gently'='URGENTLY'
'but' is the link.
Can you help me to learn more?
(Other definitions for urgently that I've seen before include "without delay" , "with expedition" , "As a matter of priority" , "Earnestly and insistently" , "Immediately, with pressing need" .)