I deep dived into the DSDTs and SSDTs for both MacPro5,1 and MacPro6,1. It seems that in MP5,1 UHC and EHC are defined, but in MP6,1 There is only one EHC1 and one XHC1 devices defined. I have a USBMap and XhciPortLimit=false, but unplug and plug oh USB 1.1 devices won't work again until boot. I...