What Beethoven did, being calm (8)
I believe the answer is:
composed
'calm' is the definition.
(similar in meaning)
'what beethoven did being' is the wordplay.
I cannot really understand how this works, but
'being' could be 'mp' (MP is an example) and 'mp' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for composed that I've seen before include "What poet did" , "What Gershwin did" , "Calm and collected" , "Made a score" , "Settled" .)