Hi Neemobeer, thanks for your reply.
It doesn't lock up completely; I can still move the mouse around, bring the Windows menu, minimize and maximize programs, etc., but the system doesn't respond to pretty much anything I do. If I try to close a program, it doesn't close. If I press Shutdown or Reboot, I'm taken out of the desktop environment and a blue screen appears saying the system is shutting down, but it doesn't do anything else, so I have to press the power button.
The resources monitor shows spikes for a software I use for work (Trados Studio 2015) and for Google Chrome, but I can't close them when this happens.
I think this may be due to a faulty bluetooth driver, since it only happens when I'm using the bluetooth speaker (it happens randomly, but it usually happens about 1 or 2 hours after I activate the bluetooth and start using the speaker).
I will try the commands you posted and I'll also upgrade the bluetooth driver to see if the problem disappears. I'll keep you posted.
Regards.