I use Ringtone Maker and have had no problems. The app is stored on the sd card so i believe that's where the mp3's are stored as well. I'm rooted though, and still running GB .9 on my tbolt.
I've seemingly tried everything I know. It's like the phone has a mind of its own. The odds of getting my custom ringtone to play for a contact is about 50/50 on a good day. I still have no idea why the phone is getting confused.
