This is should have been fixed in Firmware a while ago, I believe everything after 53.20.41 has it fixed.
Latest firmware is 53.23.03 and is located here.
Give that a go and see if it resolves the matter.
Several WC 5325s at my sites have the habit of entering sleep mode, then not waking up when I press any buttons or send print jobs. I have to shut off the machines, and reboot them.
I'm fully aware I can alter power saver/low energy timers online, but that does nothing since I have no idea how to solve my problem using those settings.
Is there some software issue causing this, or some other issue with settings that aren't obvious?