I bought a cable on the 1st August this year. Post a pic of yours and I'll check if there are any differences. Apple has been changing the dock connectors on recent ipod upgrades and breaking the usability on previous accessories. eg iPhone 3G has got a different connector to 1st gen iPhone.
My cable works fine with 5th gen video. My 1st gen iPhone states accessory is not supported but still works.
Apple are becoming the new Microsoft
