at the lighdm login screen i can successfully sleep my pc (suspend to ram) and once it's asleep pressing any keyboard key will wake it up again, as expected.
however, once i am logged in to kde, i can sleep the pc, but once it's asleep i cannot wake it up again!!
pressing any keyboard key or the power button or a mouse button all do nothing, the pc stays asleep...
i have 'lock with a password when waking from suspend/sleep' turned off.
the only way to recover from this 'sleep of doom' is to hit the reset button...
so, why does waking from sleep work fine in lightdm but not when logged in to kde??
any help much appreciated.