I love my Chromecast however I can only get sound from the tv speakers. I would like to use my wireless headphones that I plug into our surround sound receiver but can't figure out how to do so. The receiver is old and does not have a HDMI port. Both sets of Audio Out on the tv are in use, one to the receiver and the other to the DVD. I have tried all kinds of setting adjustments to no avail. Any help would be greatly appreciated. Thanks!