I can not get most of the new MPEG4 HD stations. I keep getting a "771" error message. I can, however, receive TNT-HD, TLC-HD and VsGLF HD just fine. All the other MPEG4 stations are blank with that message. My locals in MPEG4 work fine as well as the older MPEG2 stations and all SD stations. D* has replaced my HR20, checked the LNB signal and the line right at the reciever....all check out fine. The installer did ask me if I had a splitter connected and couldn't remember as it would be in the crawl-space of my home. However, if there was a splitter, there'd be no MPEG4 stations at all and the tech's meter would show it when connected to test the line. What else could it be? Any ideas?