AirPlay doesn't work with Apple TV home hub enabled

I haven't been able to use AirPlay from my iPhone to Apple TV for the past 3-4 months. Actually, no AirPlay devices in the house work (Apple and 3rd party). When I use a media application, such as YouTube and attempt to cast a video via AirPlay, the play/pause button appears to be unresponsive. Nothing plays. Screen mirroring works, but when full-screen videos attempt to handoff, videos never actually play.

After extensive troubleshooting (restarts, updates, restarting network equipment, toggling AirPlay on and off, etc.), I found that disabling Home Hub fixes AirPlay (which breaks my automations, as I don't have another hub). For whatever reason, disabling home hub also fixes non-Apple AirPlay connections (such as smart TVs with built-in AirPlay).

Has anyone else experience this? What steps am I missing?