Does it also happen with the network card directly plugged into the header and no splitter?
directly plugged is fine. instead the 9 pin header splitter not work in 11.6.6 update, Bluetooth keyboard can be use in opencore boot menu and windows, while boot up to Big Sur 11.6.6, the spiltter only provide front usb panel, bluetooth not working after bootup. it show bluetooth not available, with grey icon
Everything fine with splitter in 11.6.5
Try direct plug to header, work fine
Using internal usb hub - not ok, only front panel works
try clear nvram, work fine but after shut down, not working again
Try fresh install 11.6.6, still the same issue
try usb mapping the header to internal - 255 , no hope, still bluetooth grey out
It believe to be software AHCI problem with internal usb hub , any suggestion to try out ?