Been having issues for a few months now with this unit again. It seems to occur when the unit is idle, the Prime 4 will lock up rendering me with the inability to use any buttons, scroll the tracks, or use the touchpad. The unit remains on but completely freezes. After I do a hard reboot (hold down power and power on again) the system works fine. I’ve also had this issue occur when playing with the unit, everything suddenly stops but lights and screen will remain on.
Is there an internal hard drive fitted?
If so try removing the drive, and see if different external drives make the unit lock up.
Might be that the type of drive goes to sleep mode when idle but won’t wake up properly when it’s supposed to