had similar problem:
this tool: Drag the tool (https://mega.nz/#!wB5GDTTR!NnZn8qZF--kpU3Zz3qQOSGj5348ELg7Jw-diSmZWujw)
to Piplay installation (C:\Program Files\Pimax\PiPlay2), and then use
it to flash the firmware.
and this firmware:
Recently we made a special firmware for Vega users after discussing with AMD side, downloading link: https://mega.nz/#!cMBzXSJC!m_3HgHjSeYJNDhUg3Qnz5zYVVl57zKhCxU19NIhJO3g14
those did the trick for my Vega64(in December), currently everything up to date and working fine.
it is an LCD screen, so there is bound to be some ghosting, i usualy only notice it in the beginning, either it gets less after it "warms up" or whatever... or i just get immersed into what im doing and dont notice anymore.... whatever the case, it isnt realy a big thing for me, i just love the resolution.