Hi Stavros,
we had a couple of feedbacks similar to your situation (we are still working on debug).
Surely a part of the problem is
the slow shutdown bug.
On shutdown you may have to wait a lot of time, especially if you use CIFS mount points, prior to disconnect the AC adapter from your RuneAudio player.
This is connected with a known bug of Systemd.
We hope to solve this problem as soon as possible.