I'm pretty clueless here. I recently got my ED64 v2.5 but it doesn't really work. I set up my SDHC Sandisk Ultra 16GB 80MB/s with the OS and roms. I started up the n64 and it booted up and i started playing. I turned it off with the power switch and next time i tried to start it up, I had [UNEXPECTED ERROR] error 91. After some experimenting I learned that deleting the OS and putting the original back onto the SD card will allow me to once again boot up and load a rom, but if I turn it off and on again the error returns. Also wanted to note that my power button is jammed and i cannot use it.