It should be under HDMI setup. There is a setting to Auto switch for TV Audio.
Have a look here: http://manuals.marantz.com/SR6013/NA/EN/GFNFSYkabkahie.php
This could also be the HDR setting. Some TV's do it better than others. Try disabling HDR on your TV and it should be brighter, at least in my experience.
Hi Vaughan
I saw on Facebook that you guys are releasing two new subwoofers. With a smaller one coming in the future. Can you share some of the details please?
I can also vouch for Bentley Acoustics. I went to have a listen at Vaughan's place in April and I was really impressed.
I now own the FS120 fronts, FC150 center, FR100 rears, and FR80 as height speakers. Amazing value for money!