Also, for more helpful information on your new AVR, review posts 3-7 in the 2015 Denon. highlight newly added device - click gears icon on bottom of window - select use this device for sound output.
Motto is - don't go messing around with your Mac's settings (especially if like me you don't know what you are doing and have to try to remember how to get back to what the settings were in the first place). If you have Dolby Digital set to ON on the cable box, but your TV cannot accept Dolby Digital audio (many cannot), there will be no audio passed to the TV, rather you would have to set Dolby Digital to OFF on the cable box. Click the + symbol on the bottom of the window. Sold me 2meter Gold plated HDMI cable for £10 ($13) - sound worked first time from MacBook Pro to both LG & Sony - felt an idiot.
I suspect I need a driver to let me send sound through the HDMI cable as. When I plug in the HDMI cable no new sound device shows up when I check 'Playback Devices' in Win10. To connect a digital sound bar with an HDMI cable (not provided): 1. Everything works great except for sound via HDMI. Looks like Hisense TVs have a problem Reset Audio Settings HISENSE TV H55B7500.
When I go to the Sound preferences, there is no HDMI device I can. I have a 2015 Macbook Air running Windows 10 on bootcamp. Local Computer shop told me my HDMI cable was the problem as it was C**P. The problem with the Mac Mini is that it is not sending sound out through the HDMI cable. Had problem with HDMI to LG & Sony TV's, only picture no sound with iLove Movies etc.