Why isn't there a composite av cable for lightning connection?

Having bought an iphone 5 and then an iPad mini I am disappointed with the sound quality from the earphone 3mm jack plug. Had I known that there would be a significant difference in sound quality compared to my iPod touch connected via the 32 bit connection I wouldn't of sold it and bought newer versions thinking they would be better. Why haven't apple released a lightning version of the av composite cable? Is there a work around that doesn't cost a small fortune in leads?