Cant Watch DVD's On My 360, Little Help?

When I tried to play a DVD on my 360 I see the opening trailers flash for a split second, the image shakes, picture goes black, dvd picture flashes again, goes black again, stays black and my tv says "not supported mode". I checked all the connetions and found that this only happens when trying to watch a dvd with the switch on the xbox A/V out on HDTV. For example, when I flip the 360 switch to standard TV mode the dvd plays fine and when I play a game on HDTV mode it plays fine, yet, when I try to play a dvd on HDTV mode the same thing happens. Is this one of the common symptoms of a defective 360?

the dvd drive doesnt support hd dvd movies only standard definition

edit//  

hence the 360 now has an hddvd addon so u can play high def movies on it 

you should'nt have to do that, i watch regular dvds with my xbox set to HD.. Maybe there is something wrong with your xbox or maybe its a pal, ntsc problem??tony_fjellborg

Whats pal ntsc?

Would any of this have to do with the component cables? Faulty or something? It's a possibility that my tv is the problem, but I highly doubt it since all the other inputs are working perfectly. The only reason I mention this is because I just grabbed my brothers xbox and tried the same thing, on the HD setting, and it did the same thing as my xbox (his xbox has never given him trouble); however, it was with the same component cables I used with my xbox. Bah, I've only had this thing for 3 weeks.

EDIT: Oh, I even tried setting my xbox to the lowest HD resolution to the highest resolution and the results were the same. The only thing that seemed to fix the problem was taking it off HDTV mode.

[QUOTE="tony_fjellborg"]you should'nt have to do that, i watch regular dvds with my xbox set to HD.. Maybe there is something wrong with your xbox or maybe its a pal, ntsc problem??sigelpwnsyou

Whats pal ntsc?

Would any of this have to do with the component cables? Faulty or something? It's a possibility that my tv is the problem, but I highly doubt it since all the other inputs are working perfectly. The only reason I mention this is because I just grabbed my brothers xbox and tried the same thing, on the HD setting, and it did the same thing as my xbox (his xbox has never given him trouble); however, it was with the same component cables I used with my xbox. Bah, I've only had this thing for 3 weeks.

EDIT: Oh, I even tried setting my xbox to the lowest HD resolution to the highest resolution and the results were the same. The only thing that seemed to fix the problem was taking it off HDTV mode.

Have you tried different movies??