I've had Gamecubes do this before.... Its usually something to do with the system freaking out over the replacement of the disc drive with something else. I installed the Pico Boot modchips into a few GC's and actually got this same message upon startup. It was usually due to me wiring in the Pico Boot incorrectly. I also had a GC that just refused to accept that the Pico Boot was its new loader and constantly gave me this error. I resolved it by using thicker wire for the power source lines from the Chip to the board. I'm not sure what you are using as a loader for this portable as I haven't seen the rest of the build, but that error is usually caused on stock consoles by a disc that can sort of be read but then can't and freaks out the GC.
Ahh didn't know you were using a stock DD. If that is the case the laser could actually be failing as well... You can try and tweak the potentiometer for the laser and see if it fixes your issue but that error is usually a sign that its time to replace the drive.
Worst case scenario would be to install Picoboot, as this will "bypass" the GC IPL either way and should get you around this error from my understanding. If you can't ever get the disc drive working again, this would at least let you use the thing until you decide to replace it!
I need a video of that if you do end up doing that!
I agree with Y2K a picoboot would be your best bet the GC lasers are reaching the 20yo mark. If you really want it to run from the disc drive your best bet would be to pull one from a known working gamecube. Also if you can throw up some pictures I'd love to see this build even if it is giving you a hassle.
This is awesome please don't destroy it! Even if it doesn't work it's still one hell of a build. I see the disc drive in incorporated very nice into the design so removing it would be a bit of a loss. I'm wondering if maybe there si a controller that has gone bad? Did you swap out the pcb that lies directly under the disc drive as well? Just trying to help you save this build!
