I must say I haven't ran into this issue. I downloaded a fresh copy of 0.8 beta 3 and ran SNES ROM's just fine (until I started to tweak settings).
To add onto that, I started having problems with SNES games freezing at random times once I began trying to tweak the Raspberry pi overclock settings and memory split in hopes to run playstation ROM's more smoothly. After the overclocking was done I had freezes simply on bootup.
I was lucky at one point and the pi booted back up, I took this advantage and turned off overclocking/memory split back to original settings but for some reason even with the settings restored, I still receive SNES ROM's freezing randomly.
I will most likely do a fresh install again and stick with it.