Im not sure what the "tv" feature is. But most competent stereo shops can turn this off for you (while possibly voiding some warranties) for a nominal fee. I know they can do it for the DVD systems that stop operation when you engage Drive for most cars.
Find the wire that goes from the back of the system to the park switch in your shifter. Then ground it out, it will work with the car running if you do that. I don't know what wire it is, you will have to find the scrematics, for your car. Hope this helps.