Are you using Alsa or PulseAudio to configure your audio settings? The Arch Wiki has extensive tips for both. You might need to set a default audio output
I am using Pulse Audio (and KDE). It's all correctly setup, it has been working for several months and it works if I downgrade kernel to 3.1, so it's a regression with the new kernel. Also, if any mods are reading this, maybe thread should be moved since 3.2 is out of testing.
Edit: It's quite weird. If I go to KDE sound settings and change them around a couple of times, after a while it works like it should. There is no consistency in this and I have no idea how to troubleshoot
Edit2: Could this be related? I know it's for Nvidia cards, but in the first comment he mentions hda_intel.chttps://bugzilla.kernel.org/show_bug.cgi?id=42567 I should probably have mentioned in the first post that my laptop is all Intel:
oscar@arch-laptop: [~] >>> lspci | grep Audio
00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)