Hello there, lembas.I've just checked that description and there's the possibility that, although my error messages are about the radeon driver, the bug might be that the system is not properly "killing" all the processes at shutdown/reboot. And that, for that reason, it takes so much time to do it.
I will test the proposed solution, when I have the time to, and then I'll say something back.
Thank you very much for your help. :)
