New distro, old kernel - Hardy's 2.6.24-22-rt kernel on Intrepid

First off, let me get this straight: I am currently reporting about my experiments with two different versions of the Ubuntu Studio distribution: 8.04 (Hardy Heron) and 8.10 (Intrepid Ibex). I'm dual booting between these two and trying to figure out which one will work better with my hardware and for my purposes. I realize this can be a bit confusing. When I will finally get this somewhat done, I'll write a summary of the pros and cons of each.

I have updated my first post, Introduction / My goals - I've re-structured the sections and added some basic information about my hardware which I guess is quite relevant to this whole experiment.

Thanks to Andreas Nilsson for putting a link to me in his blog!

What I did today
I did what LDiablo][ suggests in his comment to the Intrepid real time kernel bug.

I downloaded the following four packages to downgrade to the old kernel:
linux-image-2.6.24-22-rt (2.6.24-22.45)
linux-rt (2.6.24.22.24)
linux-restricted-modules-2.6.24-22-rt (2.6.24.14-22.53)
linux-restricted-modules-rt (2.6.24.22.24)

...and istalled them with dpkg --force-depends. I'm not exactly sure why I would need the restricted drivers, though.

The system boots up fine, but without ALSA. No sound at all, in other words.

qjackctl says the following:

13:45:02.348 Could not open ALSA sequencer as a client. ALSA MIDI patchbay will be not available.
ALSA lib seq_hw.c:457:(snd_seq_hw_open) open /dev/snd/seq failed: No such file or directory


Also, when trying to use real time mode:

cannot use real-time scheduling (FIFO at priority 10) [for thread -1210079568, from thread -1210079568] (1: Operation not permitted)
cannot create engine


I have a vague memory of fixing the latter issue before in Hardy - it obviously has something to do with permissions. Googling will probably do the trick. I'm more concerned about ALSA.

lsmod |grep snd gives me nothing, and when trying modprobe snd_seq I get the following message:

FATAL: Module snd_seq not found.
FATAL: Error running install command for snd_seq


I'll take a break now for a day or two. Any and all suggestions are welcome!

I'm quite surprised about acutally having readers/commenters already - thanks for contributing, and have a happy new year!

First steps - I've got sound!

I have now installed Ubuntu 8.04 (Hardy) on my laptop. Sadly, Hardy's ATI drivers for Xorg don't seem to support my ATI Mobility Radeon HD 3400, so I have to run proprietary drivers for now.

One possibly good piece of advice for anyone looking into Linux audio (or Linux in general) is "don't buy a laptop model that's too new!" or you will need a load of patience to hack around with it - sure, Ubuntu 8.10 recognizes most of my hardware, but in this case, I need to run 8.04 to get real time capabilities.

After some googling and hacking (among other things, I followed this thread about making Jack work in real time mode) I can now get sound through the Edirol FA-66. FINALLY!

Everything's not fine, though. Jack has crashed a couple of times during the last 20 minutes, Qjackctl seems to be inclined to freeze, and there is some annoying crackling and popping going on during playback in Ardour - although neither Qjackctl nor Ardour registers xruns (Ardour does, however, detect "spikes" in master output).

On one hand, I'm glad that I've gotten this far. There's definitely a sense of accomplishment, and I'm hopeful about this whole project. On the other hand, there are obviously some issues to be dealt with before I've got a stable, working setup.