I have the same problem. Mine is a bit older. It's also an Omnivision, but it's about 6 years old, and just a TV VCR Combo. It has worked very well for this entire time, and all of a sudden, 2 days ago, this big black box covers up 90% of the screen. If I make anything happen on the screen (IE: Click info on my satalite, change channel, look at time) The box vanishes for as long as the task is performed. In other words, I click time on my remote, the black box vanishes, the time and date go up, and stay for about 5 seconds. When the time and date finally go away, the box comes right back.
This happens when I watch TV or VHS, or even when I plug in my DVD player.... Very odd. Tubes going out or something??? Can't afford a new TV at the moment.
Kyle, May 2006