### Clue: Orchestra misbehave — less authentic in audition (8)
### Answer: SINFONIA 
 ### Explanation: Definition: Orchestra

**SIN** ("misbehave") + homophone [*in audition*] of **PHONIER** ("less authentic")
 
*I can't think of an accent where PHONIER sounds like FONIA, but I've given up arguing about homophones.