Originally Posted by jaegertc
1. STB is Sci Atlantic 8300HD
That's not the one I have so someone else will need to help you with checking it's configuration.
2. Currently connected to AC power via power strip (not conditioner). I have already mentioned that they may want to invest in at least one of the smaller conditioners (know of an alternative to Monster?).
Line conditioning can be witch craft with Monster leading the ritual. There are threads dedicated to surge protection, line conditioning, and uninterrupted power supplys.
For your current problem, which is probably a ground loop, one thing to try is connecting the TV and the STB directly to the wall. The objective is to eliminate as many variables as possible.
3. I'm not aware of any electrical motors on circuit, but it is a possibility given that this is in a great room.
Can your dad determine exactly what's sharing the great room circuits? Hopefully it doesn't include a refrigerator in the kitchen or a bar.
4. Yes, there are old TVs connected within the house, so...what do we do with that?
I ask because it's possible the cable STB is still configured for one of the older TV sets.
5. If I have them redo the HD setup for the SciAtl box, do I have them NOT keep interlaced and 720p settings?
That part of the configuration probably isn't involved in the scrolling problem. Some people force all output from their STB to one resolution. That doesn't give them the best possible picture quality, but it avoids a delay when the TV has to adjust to a new resolution.
Others set their STB to pass on all incoming resolutions to the TV unchanged. Theoretically that will give you the best PQ, but for many of us it's a small difference.
There is also an option that tells the STB which shape screen it's connected to. The old TVs are probably 4:3 screens while the new TV is definitely a 16:9 screen. Again, if that setting is wrong, it's probably not causing your problem, but I would check it if you don't know for sure that it matches the new TV.Blasst
seems to have more ground loop experience than I do. His suggestion to switch to HDMI or a DVI to HDMI connection is a good one. The type of cable you will need depends on the STB. It should have either a DVI or a HDMI output. Other owners will know for sure.
A good source for excellent cables is www.monoprice.com
who is a sponsor of AVS, and has prices much lower than Monster.
Blasst and I both asked about a DVD player. If your parents have one it would help to know how it's connected to the TV, and if there are any PQ problems when they use it.