One thing I can think of that may be causing your lock up is SD fragmentation. To fix that, copy the contents of your SD to the computer, format the SD and copy everything back. That will effectively defrag your SD.
I've played the game on r4 1.18, YSMenu, and Wood R4. Since R4 is the worst card... If it can play all the EBA songs without freezing, then you will have NO trouble playing it on any flash cart out there.