Ok cheers, will try that.So as I said, despite the misleading name I think the surround mode applies upmixing on non-Atmos Dolby tracks and DTS Virtual:X on DTS tracks.
It's still great on what ever setting to be honest.
Has Dolby decoding chips improved in the last 15 years?
Managed to confuse the Vizio when I kept rewinding The Last Jedi 4K. Sound went off. Had to power cycle. It kept doing it though, until I just used skip back 10 seconds on the Panny remote.