Flattery may be sort of tasteless, and intended to be heard (12)
I believe the answer is:
blandishment
'flattery' is the definition.
(I know that blandishment is a type of flattery)
'sort of tasteless and intended to be heard' is the wordplay.
'sort of tasteless' becomes 'blandish' (somewhat bland).
'and' says to put letters next to each other.
'intended' becomes 'meant' (to mean something is to intend it).
'to be heard' indicates a 'sounds like' (homophone) clue.
'meant' sounds like 'ment'.
'blandish'+'ment'='BLANDISHMENT'
'may be' acts as a link.
(Other definitions for blandishment that I've seen before include "flattery" , "blarney" , "Wheedling" .)