Choppy frame rate through AV cable
I recently got a v1 iPad and, not wanting to pay the somewhat outrageous cable prices direct from Apple, bought a composite AV cable (the sort with the red, white, yellow plugs for an old cathode-ray TV) online for half the price.
Now I'm playing AVI files through the CineXplayer app. On the iPad itself these play pretty smoothly. However when I hooked the cable up to my TV it just mangled the frames, almost like it was skipping every other frame. The result is that everything jerks, really fast, and it's basically unwatchable.
I just need to know whether this is likely to be the fault of a sub-standard cable or whether it's caused by something else, such as the fact I'm playing through an app rather than directly through the iOS. Or are composite cables generally a problem for the iPad. In other words I need to know if I've got grounds to send it back to the vendor, and whether getting an "official" cable will fix the problem.