Yesterday I spent most of the afternoon and evening trying to fix the Arch Linux installation on my laptop (a MacBook 7,1). It had broken a while ago, back in October, after a kernel update. I got a kernel panic on boot, then it couldn't find the hard drive (!!!), and couldn't complete boot. I tried to roll back the update in October but it didn't solve my problems. I waited for some weeks and yesterday I updated the packages instead of rolling back. Maybe the issue had been solved automagically?
Unfortunately, it hadn't. The kernel panic was still there. I attempted to reinstall Arch again, but it just dumped me into a black grub screen. It came to a point where I was just lost in a myriad of tutorials, hints and forum threads, and really, really confused about grub, grub-legacy, efi, efi 32, efi 64 but more like 32, efi 64, not efi, and FSM knows what.
Since nowadays I am not that interested in tinkering with linux internals--I just want a decent working Linux system, I thought I could try Fedora. I downloaded and burned Fedora 16, ran through the installation procedure and presto! I had a nice Fedora Linux installation that integrated nicely with Mac OS's odd EFI boot screen and etc etc. Everything worked nicely until I installed the proprietary NVIDIA driver to get proper hardware acceleration and WebGL support. And then I couldn't launch GNOME anymore!!! Oooh booh! I felt quite sad, as it was looking so nice and promising. But hey... at least I solved a mystery that had been haunting me since a long time ago. Dear readers, please allow me to liberally quote this page:
If your laptop has a red light coming out of the headphone hack this is the optical out. You can turn it out by running alsamixer on the command line, hitting (Fn+)F6, choosing your sound card, arrowing over to S/PDIF, and hitting M to mute it.
Therefore I was back to square one--without a working Linux install on my laptop, but at least I had discovered why all our macs exhibited that red glow when running Linux!