Sony Bravia 32 using VGA with Xbox 360 problem

Hey.

I'm experiencing problems with my Sony Bravia 32" LCD (HD-ready) screen while being connected tomy xbox 360, using the VGA cable.

I put the resolution to 1360 x 768, which is the max the TV would allow me.

When playing my games, watching video's orwhile watching the dashboard,time to time, thepicture turns black and it says: No Sync.

And after a few seconds, the picture comes back.

This is very anoying, and I hoped someone knows what this means, and can help me with it?

Thanks