I have my DCT-2000 digital cable box hooked up to my SP-1.7 by the digital output only. Sometimes (very rarely) my SP-1.7 won't lock onto the signal from the DCT-2000. If I switch to another input and back to the TV/SAT input, the SP-1.7 always locks on. I'm thinking that this is a problem with my DCT-2000 and not the SP-1.7. I haven't had this "problem" since the cable company upgraded the firmware in my DCT-2000 a couple weeks ago. If possible you might want to check your TV or Sat box with another processor to narrow down where the problem is ?