I have been fighting through an HDMI audio problem in view of the fact that I have position this computer together a week ago. I have encompassed a GTX 460 and am utilizing the mini-HDMI to HDMI cable to plug into my Harman Kardon AVR247 receiver. That with the intention of then sends the signal to my Optoma projector, as well as the encircle system hooked up to the receiver. At present when I go to the NVidia control panel and position it to organize the dual display to extend the desktop onto the projector and endeavor to configure the sound apparatus, it demonstrates a Harman Kardon AVR in my devices, other than regrettably, it determine to not permit me to make the it the default device for the reason that it says that it is "Not Plugged In", even though it observes it there. I feel it's significant to note that to facilitate the device is scheduled under the "Set up Multiple Display" Menu as "Optoma" at the same time as the projector is powered on.