Accessory not supported by iphone?

Iv had the Auvio cable that allows me to watch tv by connecting my iphone4 to the tv for months and its always worked but 3 days ago it started saying that the accessory is not supported by iphone when i used to watch tv just fine? What could it be?

It just mean that it is not recommended or made for iphone, but it still will work.

It should still work, but it means that the cable isn't working right with the iPhone. It's probably damaged or the company made that product really poor quality. Or Apple just doesn't support that company.