If you have enabled the sleep mode option, as shown below, it might happen that the machine does not wake up after xx seconds. If you press the power button the device will shut off. 

In this case you have to change the 'Block Sleep' in the BIOS and check the box for "Block Sleep (S3 State).  Reboot the machine and load the software, now it should wake up from sleep mode. 

Sleep mode example setting: 



Screenshot from the BIOS: 

If you still encounter issues with the sleep mode options, please contact us at support@global-emea.com