It is more detailed and suggests the source of the problem; it also seems that the bug occurs in many more machines.
The suggested fix there (for a Dell XPS) is to install linux-backports-modules-alsa-karmic-generic or linux-backports-modules-alsa-karmic-generic-pae (depending on your kernel).
However, this did not work for my Lenovo X300, so it's not resolved yet, but maybe somebody can use the information to construct a solution for the Lenovo's as well.
I think this bug is related to this one:
https:/ /bugs.launchpad .net/ubuntu/ +source/ linux/+ bug/418617
It is more detailed and suggests the source of the problem; it also seems that the bug occurs in many more machines.
The suggested fix there (for a Dell XPS) is to install linux-backports -modules- alsa-karmic- generic or linux-backports -modules- alsa-karmic- generic- pae (depending on your kernel).
However, this did not work for my Lenovo X300, so it's not resolved yet, but maybe somebody can use the information to construct a solution for the Lenovo's as well.