Thanks all for your replies which turned out to be wise :-)

As you surmised, the firestick 4k isn't passed through by the HD621 so either I replace the Meridian HD621 or send the firestick direct to the TV and switch the TV between the HD621 & Firestick. We all bought the HD621 to avoid this complexity :-( !!

And the price of the UHD722 bucks the trend for electronics to become cheaper every year. Come back, Mr. Moore!


Again, thanks all and happy listening.