Won't sleep issue - Solved!

For those of us that use a RealTek sound chipset on a motherboard, there is an issue when using the Line In port. If you enable this feature, this will prevent your PC from going to sleep.

Here is a screenshot of the port enabled, showing the stream is prevent sleep:


I disable the port, reboot, and now there is no audio stream blocking the PC from sleeping:


Hope this helps. I'm considering disabling the Realtek on my motherboard and go with a sound card.

Have you tried adding a powercfg requestsoverride for the Realtek request to see if that will allow sleep ?
That works for me in Win 7, i don't have the request in Win 10.

The RequestOverride for Realtek doesn't work. Frankly, driver support for Realtek is crappy. I just got the SoundBlaster ZX and will install it this weekend. I've learned that video/audio on the motherboard is a poor solution for many folks. I have a separate video card (NVIDIA GeForce) that has performed flawlessly.

Final note: seems that having Line In set to Listen will open up a process that prevents Windows from sleep - this happens even with the SB card. Easy to turn off, but a pain to have to reset every time want to use it.