Problems with S3 on 5i5RYH (Win 10)

Hello all,

I have recently purchased a NUC5i5RYH and subsequently installed Windows 10 after fitting it with a 2.5" SSD, an M2 SSD and 16Gb or Hyper-X memory.

Other than this problem, the system appears to operating normally.

I am unable to get the system go in to S3 state. I have tried various power options permutations, consulted and implemented the strategies on these posts...

NUC5i5RYK will not sleep in Win 8.1

i5 NUC Won't Sleep: Win8.1

...but cannot get the system to sleep. The system will turn off the screen, but power is still on (power LED is solid) and there is SSD activity. I have also confirmed that the system is not sleeping by connecting it to a energy monitor, whereby it is still exhibiting low activity power draw (>8.5W)

The system is fully up to date with updates and is running BIOS version RYBDWi35.86A.0350.2015.0812.1722 .

Any suggestions as you why my system is not sleeping and how I can get it to do so?

Many thanks.