Ok. this happend here too ! Burned in 8x in a good media but got the #001.(srry for my english)
What i did (and dont know why worked):
Booted freeloader and tried to run the same disc that was givin me error, and worked! No #001 after that, and no need to boot freeloader everytime. Dont know why, but this worked for me.
Wii 3.2E + wiikey 1.9s with dev mode on and block mode on.