Capital city of Doha, noisy somewhat (5)
I believe the answer is:
hanoi
'capital city' is the definition.
(I know that Hanoi is a capital city)
'of doha noisy somewhat' is the wordplay.
'of' indicates the answer is hidden within the clue.
'HANOI' can be found hidden inside 'doha noisy somewhat'.
(Other definitions for hanoi that I've seen before include "Vietnamese capital" , "Asian city" , "foreign city" , "Vietnamese city" , "Asian capital on the Red River" .)