I recently purchased an Insignia NS-55DF710NA19 and I’ve connected it to my Cambridge Audio receiver via HDMI and Optical but I’m getting no option to route my sound to the receiver. When I go to audio output in settings, it just gives me the options to turn off my TV speakers and change the digital audio format. I’ve searched high and low for an answer but haven’t come up with anything so I figured I’d give this a try.