Original problem solved. Like Saurian said, it was in S-Video mode. I'm an idiot... I thought that I had checked that. Oh well... Thanks for the help - all of you 
-----------------
New Question! - 14/7/03
My friend has an XBox, unmodded PAL which he uses as a DVD player. I assume that he is using the default composite lead that comes with the console, I think he's got the Phillips drive in the console (From vague description).
When he plays games the picture is fine, but when he plays DVDs apparently the screen gets brighter and darker every few seconds: "Like the sun keeps hitting the sceen and going again!"
I'm going to give him my composite lead, see if that works... He said that he's tried wiggling the leads and stuff... it's just still not working properly...
The fact that it plays games fine is the weird thing!
Any ideas?

-----------------
New Question! - 14/7/03
My friend has an XBox, unmodded PAL which he uses as a DVD player. I assume that he is using the default composite lead that comes with the console, I think he's got the Phillips drive in the console (From vague description).
When he plays games the picture is fine, but when he plays DVDs apparently the screen gets brighter and darker every few seconds: "Like the sun keeps hitting the sceen and going again!"
I'm going to give him my composite lead, see if that works... He said that he's tried wiggling the leads and stuff... it's just still not working properly...
The fact that it plays games fine is the weird thing!
Any ideas?
Comment