Getting 775 error

I recently started getting a 775 error. The picture would freeze and sometimes go black but it would come back on. This started happening more frequently. I've followed the cable and all connections look fine. I'll reset the unit and it will work again.

Also, most of the programming we watch is recorded. We're experiencing frequent freezes in the play back picture lasting a couple of minutes or more and then the picture returns but we've lost all programming in between. The frequency of this happening has increased as well. 

What's going on?