I just realized that the title may be misleading. :/

I'm pretty sure this is due to a bug in the libfat library which snes9x-gx uses.

confirmed

this probably happen because each time you write to SDCARD, the card is
unmounted/remounted

libfat *probably* does not like this very much, maybe there is some kind of 
memory
leak or stack overflow which results in a crash

I have same issue, It's effecting all of the latest emulators. Maybe make you go
through menu to unmount first?

I thinks its the "hot swapping" issue

Why do you have to unmount/remount with each write? Isn't that a bit excessive?

I'm aware of this issue and I'm waiting for some changes the libfat/libogc guys 
are 
making to fix this. unmounting/remounting happens because at the moment there's 
no 
way to determine if a device needs the remount - so I do it all the time. 

Ya when I ran into this I was sad.  I was in the middle of Sigma in MMX3 (ty 
for the
Toxic Seahorse fix!)

I have this problem too, but not the freeze problem.  I had this problem in VBA 
GX, too.  
VBA was fixed when I downgraded it back to the previous version.  Is it 
possible to just 
release a version without the new libfat?

Yep, I can confirm this problem; "can't" find the SD card and then a lockup. 
Forced
to reset Wii.

Yeah, this happens to me a lot as well. Sometimes I am able to shut off my Wii 
when 
it happens, other times I have to do a hard reset.

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