ringtone reset

My Tour mysteriously reset all the contacts with the default ringtones to classic ringer. It didn't touch any with an assigned ringtone. When I change the default, it accepts it on the phone, but doesn't change any contacts' ringtones. It appears it made the classic ringtone an assigned ringtone for everyone! How do I erase all assigned ringtones without doing it one by one? Otherwise I have to go thru 200 contacts, and will have to do this every time I want to change a ringtone.

Thanks

This same thing happened with my Tour. I haven't figured out how to fix it yet.