Enabling Audio controls
By default, the sound may be disabled and the volume control buttons on the laptop (up by the ThinkVantage button) and the volume control applet (up by the clock) will not control the speaker volume (they actually control the microphone). To fix this:
1. Right-click on the volume control applet (by the clock) and select "Open Volume Control"
2. In the "Switches" tab, make sure "Headphone" and "Speaker" are both checked.
3. Close the Volume control.
4. Right-click on the volume control applet again and select "Preferences".
5. Make sure the device is set to "HDA Intel (Alsa mixer)" and highlight the "PCM" option.
6. Close the preferences.
7. Select System->Preferences->Sound.
8. In the "Default Mixer Tracks" section, make sure "PCM" is highlighted.
9. Close the sound preferences.
You should now hear sound and be able to control the volume using the laptop buttons or volume applet.
A recent BIOS update  fixes the mute button, you can then configure it to mute/unmute audio in Keyboard Shortcuts.