Yes, that's changing the aspect ratio on my TV. I can't change the ratio on the Zappiti as the menus are off the side of the screen, though maybe I could try and find out what the menu structure is and try navigating blind to the aspect ratio options to see if that changes anything!When you change the aspect ratio on your screen, is that via the TV itself or through the Zappiti menu while playing the content? Unfortunately in more recent versions they stopped auto-adjusting aspect ratio, so you have to manually go into the menu while playing content and adjust it from there.
If that's what you've already done and the overscan calibration all checks out, I'm not sure.
It's weird, when I first start a video I've noticed that a get a brief flash of the image at the correct proportions then it switches to the incorrect size. I've tried forcing the display settings to various ones, rather than relying on auto, but that doesn't make a difference.
Yep, overscan all looks OK, I can see the green box at the edges of the screen, and oddly, the test pattern videos all look OK as well. I don't believe the issue is with my videos though as I have tried various different ones including mkv rips and straight DVD copies of the video_ts folder and all show exactly the same issue, and they all look fine on other players.
UPDATE - After noticing that there was an aspect ratio button on the Zappiti remote I thought I'd try that, booted up the player, started a video and it was fine! So don't know what the problem was but seems it's just resolved itself over night, hopefully it wont come back!