From Matrix chat, when in non-display grouped mode, media player entities do not have functioning "play" and "next track" buttons in the Home Assistant skill dashboard.
I spent a bit of time on this and I suspect what we're seeing here is that the device state is not updating in an appropriate amount of time for Qt. However, I don't know Qt, so a fix here may take some time.
From Matrix chat, when in non-display grouped mode, media player entities do not have functioning "play" and "next track" buttons in the Home Assistant skill dashboard.