I have to admit that my DCT-6412 is working much better now. So much so that I cancelled my service call to have it replaced (also out of fear that box #2 might be worse than box #1). It is now recording series, and most importantly, giving a reliable playback of the recordings. It is also giving reliable play back on rewinds of live TV (good for replays or missed dialogue).
I tried several things: first I added a signal booster (from Motorola); then I removed the splitter for internet (put it upstairs on another line). Neither of these solved the problems (although the quality of live TV may have improved).
Finally, I decided to reduce the number of digital outputs from the box to the TV. I had an HDMI/DVI cable, a component cable and a firewire cable all hooked in. When I removed the Component cable only, the playback quality did not improve. When I removed the firewire cable the problems stopped. It is already known that the DCT-6412 does not fully enable firewire. Firewire on this box does not support VOD nor even the guide (seems to not be fully bi-directional). Removing the firewire cable allows the DCT-6412 to record and playback just fine with either component or HDMI/DVI cables. So, even when not in use, the firewire cable interferes with the performance of the DCT-6412. I will only use the firewire to record directly to my Mitsubishi WD-52825's DVR (or to another device like a computer) either live TV or shows recorded from by the DCT-6412. Otherwise it won't be plugged into the DCT-6412.
Wayne
I tried several things: first I added a signal booster (from Motorola); then I removed the splitter for internet (put it upstairs on another line). Neither of these solved the problems (although the quality of live TV may have improved).
Finally, I decided to reduce the number of digital outputs from the box to the TV. I had an HDMI/DVI cable, a component cable and a firewire cable all hooked in. When I removed the Component cable only, the playback quality did not improve. When I removed the firewire cable the problems stopped. It is already known that the DCT-6412 does not fully enable firewire. Firewire on this box does not support VOD nor even the guide (seems to not be fully bi-directional). Removing the firewire cable allows the DCT-6412 to record and playback just fine with either component or HDMI/DVI cables. So, even when not in use, the firewire cable interferes with the performance of the DCT-6412. I will only use the firewire to record directly to my Mitsubishi WD-52825's DVR (or to another device like a computer) either live TV or shows recorded from by the DCT-6412. Otherwise it won't be plugged into the DCT-6412.
Wayne