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.
<img src='http://members.cox.net/inelson5/330i.jpg' border='0' alt='user posted image' />
<img src='http://members.cox.net/inelson5/wooani.gif' border='0' alt='user posted image' /> The whistles go WOOOO!!! *BUBB RUBB FAN CLUB*