courtesy: David Sullivan/Kansas City Symphony In December, Kansas City Symphony musicians are usually playing in the pit during performances of Kansas City Ballet's "The Nutcracker." This year, they're offering a musical Advent calendar, including music from the show. The coronavirus has Kansas City Symphony musicians mostly playing their instruments at home these days — and creating music for online audiences. In a normal year, December would be the craziest month for the musicians of the Kansas City Symphony. The orchestra performs in its own concerts at the Kauffman Center for the Performing Arts, including Handel's "Messiah," as well as in the Kansas City Ballet’s "The Nutcracker."