Your hotel is a mere five minute walk from downtown Salzburg, so sleep in a little this morning to prepare for the music festival. At breakfast, prepare yourself for a treat. In addition to the normal Germanic breakfast fare, you'll get to eat a slice of Zopfbrot slathered with Nutella, a treat you won't want to miss.
You will participate with other musical groups in the Silent Night music festival. You'll be able to sing inside with a good audience and a nice accoustic. You'll also take time to listen to the other groups performing in the festival.
After the festival you'll have some free time to find a bite to eat. Look for a Dönerkebab stand. It is a gyro sandwich chain that is the craze of Austria. You'll then be able to participate in an optional activity of your choice: The Sound of Music Tour, a visit to the Marionette Theater, or a tour of the Hohensalzburg fortress overlooking town.
Get together with the other participants in the Silent Night Festival for a mixer at the Stieglkeller Restaurant, located on a winding road halfway up to the Hohensalzburg fortress. After a cold day outside you'll enjoy a steaming bowl of soup and delightful dinner overlooking the city of Salzburg.