Minor steam issues (sound) on OpenSUSE 12.3 x64

Hello,
Novice user here, still learning and experimenting. I had been using 12.2 x64 for quite some time, and steam worked great there. I Recently did a fresh install of 12.3 x64, and among some sparse minor problems, steam has a few issues. With default settings steam doesn’t connect to pulseaudio. There is sound, but I noticed that if I have pulseaudio streams on (eg music player) either steam won’t output any sound, or the streams will refuse to play.
Some related(?) output of steam console:

PulseAudio connect failed (used only for Mic Volume Control) with error: Access denied

ALSA lib pcm_dmix.c:1018:(snd_pcm_dmix_open) unable to open slave
[0604/001601:WARNING:alsa_util.cc(24)] PcmOpen: default,Device or resource busy
ALSA lib pcm_dmix.c:1018:(snd_pcm_dmix_open) unable to open slave
[0604/001601:WARNING:alsa_util.cc(24)] PcmOpen: plug:default,Device or resource busy
[0604/001601:ERROR:reference_audio_renderer.cc(45)] Not implemented reached in virtual void media::ReferenceAudioRenderer::OnCreated(media::AudioOutputController*)

AL lib: pulseaudio.c:612: Context did not connect: Access denied

The only way I found to get proper sound in the steam window - and for its games to appear as clients- is to run steam with STEAM_RUNTIME=0 and SDL_AUDIODRIVER=pulseaudio.
However, now I’m facing other problems, like left 4 dead 2 complaining about “could not load library matchmaking” and exiting. This does not happen without setting steam runtime to 0.

I wonder if I broke anything in pulseaudio, because the first thing I did after my install was try to tweak the sound with equalizers (my speakers’ low-end is excessive by default). I tried qpaeq with poor results and now I’m using LADSPA as the default sink. Steam is the only application that has problems with pulseaudio though.
I’m quite fond of pulseaudio, and wouldn’t like to disable it altogether, as some workarounds suggest.

Has anyone else had similar problems with steam? Thank you for any assistance.

bump.

I’ve been trying to troubleshoot my issue, because so far L4D2 and Trine2 don’t work with STEAM_RUNTIME=0 due to some obscure dependencies provided by steam itself, and since I’d love to play those games, I must leave it set automatically at 1.
The weirdest part is, some games (eg L4D2) play sound normally and show up at kmix as pulseaudio clients, while others (eg Trine2) don’t connect to pulseaudio, they may or may not output sound, and if they do, pulseaudio streams refuse to play.
How come, if I manually set the steam runtime to zero, ALL games (except the forementioned anyway) connect fine to pulseaudio?

I’m considering reverting to an OpenSUSE 12.2 installation, where steam worked great.

I’d really appreciate your feedback. Do you use steam on OpenSUSE 12.3 x64 with no sound issues? Do you use pulseaudio? Do all steam games connect to pulseaudio? How do you launch steam?
[HR][/HR]
Slightly off-topic: I’ve googled extensively, and of all the issues and solutions I found and tried so far, one is very similar to what I’m experiencing: No sound after latest steam beta update · Issue #1179 · ValveSoftware/steam-for-linux · GitHub
There, an odd suggestion appears which apparently helps some users.

                    Try this:

ls -l /var/lib/dbus/machine-id
ls -l /etc/machine-id
If /var/lib/dbus/machine-id doesn’t exist and /etc/machine-id does, do this:
ln -s /etc/machine-id /var/lib/dbus/machine-id

This is really bizzare. From what I gathered from manpages, machine-id is a unique identifier of my PC calculated at installation(?). On my system, both those files exist, but they show a different hex. (Is this normal?) The suggestion however, involves linking, so the same content is referenced in both locations. Since I am oblivious to the underlying mechanics involved, I don’t know if I should try this. Could it be damaging to my system?

Any insight will be much appreciated.

HISTORY
The simple configuration file format of /etc/machine-id originates in the /var/lib/dbus/machine-id file
introduced by D-Bus. In fact this latter file might be a symlink to /etc/machine-id.

Encouraged by the above manpage contents, I tried the previous post’s suggestion with success.

Solved by backing up the old /var/lib/dbus/machine-id, and replacing it with a symlink of /etc/machine-id. Steam and its games now connect to pulseaudio without any need to set variables.

I still don’t know how or why these two files ended up being different on my PC, if there is any significance to their difference, or if the replacement puts my system at risk. I read somewhere that some gnome apps rely on this number and they could potentially break if changes were made. I use kde4 and xfce, and I haven’t noticed any abnormalities so far.