EDIT: Ok so here's what I think is going on. I receive a communication error when trying to trade in the union room in Soul Silver to my retail version of Diamond. I learned that this isn't the only game with this problem. I got Chinatown Wars onto my flash cart and tried playing a multi-player game with my retail version and received a similar error where the game disconnected when starting the game. So i realized that only game that utilize multi-card play are having these problems. I tried New super Mario Bros., Sonic Rush Adventure, Mario kart DS, and SM64 DS. All of them worked fine. BTW I have: R4i-Advance (DSTT clone) running latest unofficial DSTT firmware (1.17a12) So how would I fix this?