I didn't go to the Windsor last year but went the year before. You could happily wander round it to see most of the items without having to book. There were some booked demos at Windsor but there were some at Whittlebury. I usually avoid them unless there is something of real interest.
The Windsor show is aimed at the High End. A lot of countries have High End shows because that is where the money is. If you want a show that is not "deadly serious", Scalford is the one.
At the end of the day, no show is perfect and the shows will have their fans. I may go to the Whittlebury show but I'm 50/50 at the moment.
All cables have differing electrical parameters. EG . Capacitance . It is foolhardy to suggest they do not effect the sound .
"Make a sound is misleading" I prefer the window analogy . Some cables present the signal as a clean window , others present a blurred more opaque representation of the electrical signal .
DTS Play_Fi will do what you need, but unfortunately only through the Windows PC app, and not through the Android or IOS apps, I'm guessing it's not a Windows tablet.
Pity because you can get a receiver for not a huge amount of money