Hi tbergman and welcome to cdfreaks,
A couple suggestions.
I "think" your player is a Pioneer AVD-W6200. I had to guess a little...
I just tried to log in on Pioneer's support site, but it won't let me access the owner's manual without a login.
I'd take a look and see what Pioneer recommends:
http://www.pioneerelectronics.com/pn..._38315,00.html
Not sure what you've tried, but Taiyo Yuden and Verbatim are your best bets for quality media and compatibility outside of the manufacturer's recommendations. Try to stick with made in Japan.
There are a lot of variables involved here: media, burner, firmware, burn speed, etc. The media that works best in your burner may not work well or at all in your car player. The marriage often involves some trial and error.