Sound Blaster Z preventing sleep

Since installing my Creative SoundBlaster Z, I've noticed that my computer won't go into sleep automatically.

This seems to be caused by using Dolby Digital Live (DDL) or DTS Connect. Both these technologies work by taking the audio going to the driver and encoding it into a surround sound digital stream for a receiver. It's constantly running, so there is always a stream open. Windows interprets this as there is music playing, so doesn't allow the system to sleep.

There is a workaround though, which applies to all Creative Sound cards.

Using a privileged command prompt, you can use the powercfg command:

powercfg -requests

will show what is currently blocking any sleeping. You'll see the sound card listed here, for example, mine is

To ignore this driver, you can use the following command:

powercfg -requestsoverride DRIVER "Sound Blaster Z" SYSTEM

Your system should now be able to sleep peacefully!