I have the WiFi version of this motherboard and having the same issue with Bluetooth and sleep. I'm using a broadcom card (not the built-in Intel one) and most everything works just fine. However, I have yet to be able to chase this sleep issue down. I've found it's 100% reproducible. The very first time you put it to sleep after a restart, it will immediately wake right back one second after my lights turn off and fans stop. It happens every single time after a boot on the first sleep. When the machine does get to sleep on the second try I've noticed it will randomly wake up throughout the day like you.
Also, when waking it up from sleep, about 50% of the time my mouse and keyboard will be frozen. My bluetooth icon in my status bar is connected still, but nothing responds and I have to do a hard restart. I initially thought it was just my mouse, hence my last post, but discovered it was the bluetooth and not just the mouse. I've tried disabling USBWakeFixup.kext & SSDT-USBW.aml and it helps with the waking up and BT freezing, but the first sleep after restart persists. It takes a lot of clicks and keyboard presses to finally wake it up though with USBWakefix off.
I've fiddled with proximity wake, USB power delivery in Soft Off state (S5) in BIOS, doubled check my USB map, unplugged all USB peripherals, Enable wake for network access is off, power nap is off... Can't figure out whats causing the wake ups and bluetooth issues.
