Desperately asking for help! I have a MacBook Pro 8,1 (early 2011) and Windows 8 64-bit. Installed with Boot Camp 5 drivers everything works but the audio. The sounds icon in the notification area gives the error: No Audio Output Device is installed.There isn't even a category for "Sound, Video, and Game Controllers" in Device Manager, so most solutions that involve that control are out of the question. The speakers work fine under OS X and when the POST chime plays. I have tried various RealTek and Cirrus drivers as well as erasing the disk and re-installing Windows and Boot Camp 5 drivers. This a legitimate copy of Windows 8 installed from an external disc drive. The only changes I made to my MBP was installing 8GB of memory and swapping the optical drive for a second drive. The Windows install is located on my SSD in the primary drive bay.