I have checked all setting on my tv, tried All the ports and tried several HDMI cables all to no effect.

Interested on other Philips TV owners opinions and where they think Philips are on pushing out a fix (if any as when I called them they, unsurprisingly, were clueless). I have followed all of the steps on xbox assist to no avail and even though the xbox will recognize that my tv is fully 4k UHD compatible it will not allow me to change the resolution to anything other than 640p (not 4k, not 720p OR 1080p). Unfortunately doing an update directly via the TV would bounce me to the latest version (although unhelpfully it doesnt advise you what version they propose to push to the TV prior to pressing 'Update'). The LEDs went on that tv on Sunday and i replaced it with a Toshiba 50' 4k uhd tv and am now experiencing the same problem. at that point i had a polaroid 1080p hd set and when i would reconnect it to my tv i Could change it back to 1080p. Would not recognize his tv anymore, the best resolution we can get out of it is 640p, the xbox wouldn't even let us change it to 1080p. I usually take my xbox one s up to my neighbours at the weekend for some gaming( he has a polaroid 65' 4k uhd tv) and it used to work fine on that up until the system update a few weeks back. I am having a similar issue at the moment.

Philips tv firmware update 42pfl7422d