Picture problems with DLP TV.

I recently purchased a Samsung HLN567W DLP TV. HDTV and DVD look fantastic. However some of the other DirecTV stations come in with ghosts/out of focus and "watery". Any thought how to fix this? I have changed my dish added a aerial and even had the entire TV replaced..nothing seems to work....any thoughts?
Well if you have a great dvd picture,we know it ain't the tv. Is there a setting for such as 480i/480p? This setting would be the one inside the sat. box.(acronym: stb = set top box) Toggle between these settings. While HD/DVD are great,going back to standard def, channels is a letdown;but it shouldn't be as bad as what you report.
How is the signal strength (indicated by the on screen display, and used for dish alignment). I think that different channels come off different satelites, and although they are close enough that the dish (oval one) can receive them all, the dish alignment may be optimized for one and be poor for the others. I believe that "Tilt" (rotation around pointing axis)is the axis to adjust for this.

By the way, although I am an engineer, I don't claim to be much of an expert on this subject, but I have just gone through the process of installing a Direct TV rig. I encountered no problems whatsoever.
Maybe it's a sign that you should turn off the TV and listen to some music.
Would those poor stations be the Hi-def ones? Do you have the Direct TV box hooked into the correct inputs on the TV?

I wonder if the DirectTV feed may be causing the problem.
I tried to watch the George Harrison tribute concert (PBS) this week via DirectTV.
The sound "snagged" about every 30 seconds (sort of like a record skipping). I got so disgusted I turned off the show.
I also see a lot of digital artifacts during normal viewing.
I just got another idea. I have read many people getting a better picture for standard def,---using the composite input instead of component.----Ok,it wouldn't make sense to me--but---try it;nothing to loose. You have to have remote selection for your inputs. Jeez; try the S input as well.
I have the Samsung 50" DLP. No better picture than what they achieve through DVI and Component. Try this. Set your regular non-hi def channels to operate on their 4:3 ratio, but still run it through your DVI input. I have Direct TV and mine looks great hooked up this way.