I observed one difference between ioreg's for the:
IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/HDAU@3/AppleHDAController@3/IOHDACodecDevice@3,0/IOHDACodecDriver/IOHDACodecFunction@3,0,1/AppleHDACodecGeneric/AppleHDADriver/AppleHDAEngineOutputDP@3,0,1,0
for the working one...