4K content, especially content with HDR information, requires extremely high bandwidth to transfer the data to your TV or projector. If your picture is cutting out or not displaying at all when playing 4K content, the most likely issue is your HDMI cable.
For a length of 5 metres or more, a high-bandwidth HDMI cable is key to smooth data transfer; for lengths of 10 metres or more, few commercially-available HDMI cables will have the bandwidth necessary to transfer high-density data like 4K HDR content reliably. That results in drop-outs or failed connections, so we recommend moving your OPPO closer to your projector to address this issue.