นัดดา

We can't set the volume by using the action "Set System Setting".
We have to use the action "Set Audio Volume".
To working with variables, it depends on headset is plugged in or not.

Speaker                         Headset Plugged
---------------------------     ---------------------------
volume_alarm_speaker            volume_alarm_speaker
volume_music_speaker            volume_music_headset
volume_notification_speaker     volume_notification_speaker
volume_ring_speaker             volume_ring_headset
volume_system_speaker           volume_system_headset
volume_voice_earpiece           volume_voice_headset

It also auto reduce the notification and ring volumes when plugged the headset.
So it's good to re-apply the volume profile when plugged and unplugged the headset.