Comment 28 for bug 477226

Could all who are subscribed to this bug, and who are experiencing the same problem as the bug reporter, please try the following:

1. Open up /etc/modprobe.d/alsa-base.conf in an editor. Note you will need to open with sudo, so you can write to the file.
2. Add the following line to the end of this file:

options snd-hda-intel model=lenovo-x200

3. Save the file, and reboot your system.
4. Test everything, including playback through the speakers, through headphones, and microphone input. Also test to see whether the speakers get muted when you connect the headphones.

If this procedure sees you with working sound, and muted speakers with headphones connected, then you can leave things as is for now. If either the speakers don't mute when headphones are connected, or you have non-working speaker/headphone playback, or microphone input, then please edit the above mentioned file, and remove the options line, again mentioned above, and reboot again.

Please report back with your findings, regardless of success or failure. If success, I will send a patch upstream to fix this problem perminantly.

Thanks for your cooperation.