This might be stupid, but are you sure you pushed the AV cable aaaaall the way in on the handheld? I know with my A330, I sometimes only push it in for two 'clicks' as if it's a stereo headphone jack, and the video is all jumbled because only part of the contact is touching, or some of the sound data is running into the video line or something...sounds silly, but I was thinking mine was broken too until I realised haha.
Otherwise you might have to return it, or, dare I say, open it and have a look at the jack (this will probably void your warranty and isn't worth it unless you know what you're looking for/how to fix it).
