Your TV might not be good enough.
I forst tried my IPTV and got it working with my Vu Duo box. It worked ok but the motion was not good - i guess the processing power of the box was not good enough.
I got a Mag256 and, with the same supplier, the motion was miles better.
One channel where you could easily tell is SSN where you have the vidprinter and the yellow banner scrolling across - it was really jumpy on the old box but with a Mag it was very smooth - almost as good as the real thing!