Blank spot in screen shortly after boot up

[Jesse Johannesen]

Something curious is happening to my NDRL - https://imgur.com/a/tynckVg - the screen goes blank in the middle, about 20 seconds after boot. This started to happen 2 week ago, even though I changed nothing, no firmware update, no cable or power changes. What could be going on?

When I push a button, the screen comes back. It does not come back on push of one of the chord buttons. If I remember correctly, it happened only occasionally in the beginning, but now it's on every power cycle. Firmware is 1.1.064. Planning to upgrade soon, I'm just wondering if I should be worried about anything else.

Weird, I haven't seen this one before, so I'll see what Steve and Darryl think and get back to you. 
Jesse