Voice Assistant Preview Edition media player freezes after TTS

I created an automation to vocally remind me to turn off the security alarm, if I’ve not already, when I change to my wakeup lighting scene.

alias: Verbal Reminder to Turn off Alarm When Wakeup Scene Activates
description: ""
triggers:
  - entity_id:
      - scene.wakeup
    to: null
    trigger: state
conditions:
  - condition: not
    conditions:
      - condition: state
        entity_id: alarm_control_panel.panel
        state: disarmed
actions:
  - action: tts.speak
    metadata: {}
    data:
      cache: true
      media_player_entity_id: media_player.home_assistant_voice_090c31_media_player
      message: Don't forget to turn off the alarm.
    target:
      entity_id: tts.home_assistant_cloud
mode: single

It works as expected, except that the media player continues to “play” (while remaining silent), instead of reverting to idle. The result is that the Voice Assistant device remains unresponsive after the automation is completed. The only fix is to unplug/plug-back-in the device.

What am I doing wrong? Thanks.

Seems this is a new, known issue with 2025.4: