Sony DVD RW + Memorex DVD-R + Audiovox MMDV4 Movies2go player not working out

I use Nero 7 Ultra Edition to back DVDs up. I have a copy of Roxio somewhere if that’s the problem. You can see the DVD player here: http://www.audiovox.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10001&storeId=10001&productId=14828&langId=-1

I can get backed up DVDs to play in all of my other players except the Audiovox in the car. Any ideas?

Try with other media, and Nero sucks, use Imgburn.