[madjockxbmc]

Thanks for the reply.

Ironically I have a fix ? well sort of.

As I said earlier apart from buying a new AVR with correct full 4K passthrough I was pretty stumped, I tried all the apps, but nothing seemed to work or if it did it would be a once all and then the usual surprise.

However I did read that mirroring the display got rid of it, I had issues with this as I had a basic DP to HDMI adapter and was using DP1.4 to HDMI 2.0b, and I never knew that was a thing so was also limited to 1080p on the phantom 2nd display, so if I mirrored with that, I would be restricted with my main 4K display to 1080p as well, so no dice there.

So after messing about longer than I needed to in hindsight and very close to buying a new AVR, I bought an Active DP.1.4 to HDMI cable, set both my displays to 4K as I had the option now, could only set the phantom one to 30Mhz max (AVR) and thought I would be limited to 30 Mhz max with primary display. 

But No, primary at 60mhz, and all good now, nowhere for any application to jump to so I think all is good now.