I had that with some of my attempts, if you watch a youtube video you will see it should only flash blue once and show the linux ready to run in gameplay.
Then it should flash blue on and off as it reads the game.
I know, i had it working in my old gamecube, but switched it to this one because it was already trimmed. I think that i somehow fried it, cuz i wired it exactly the same, and have no shorts.
if you have a wii, test it on that to verify the modchip is still functional...
if everything works as expected on wii, then it most likely a wiring issue or a possible issue with the trim...