iTunes loses AirPlay connection after Windows computer sleeps

Windows 10, iTunes 12.9.0.167, Apple TV 4, Apple TV 3, Philips ad7000w speaker

When my computer goes to sleep, iTunes will usually be unable to reconnect to the AirPlay devices when it wakes again. The iTunes AirPlay list still shows the devices, as shown in the photo below, but they are not connected. Unchecking the checkboxes removes the items from the list. The only way I have found to reconnect is to reboot the entire computer. Restarting iTunes etc doesn't help.

What is causing this? What can prevent it? Are there any solutions that don't involve rebooting everything?

Message was edited by: adamcohn