I think this has something to do with a custom stage(I don't have any) or something like that. I just deleted the smash stack exploit stage thing and will now see if it works.

Okay I think I found something that could be a huge step to fixing this.  When I just play brawl without ANY codes(just through the disk) it freezes, ONLY IF THE SD CARD IS IN THE SLOT, if it's not in there it works like a charm.  Hopefully this helps.

I'm using the code from MASTERLINKX Custom Brawl Pack.

<a href="http://www.youtube.com/watch?v=Pyx2U2Ff3EI&feature=player_embedded" target="_blank" class="aeva_link bbc_link new_win">http://www.youtube.com/watch?v=Pyx2U2Ff3EI&feature=player_embedded</a>

.  At one point it worked fine, but it was like a few months back, I don't remember what caused it, maybe I should just redownload the code.

  No, to the second post.  It's just stage select offline, the stages are perfectly fine online.  Offline when I press start after selecting characters and such the clapping and applause occur and then it freezes as soon as they finish.  So because of this I have to use random stage select from the menu and customize the random stage selection.  It works fine online.

When I try to pick a stage off of wifi stage select freezes after the clapping and cheering for pressing start stops.  It works perfectly fine on wifi.  I do have special stage icons, stage textures, menu textures, music hacks, and character textures.

If I do this on wifi will it desync? It looks amazing so I really hope it doesn't.