Dear Sonos Customers,
Please be advised there is a problem on OS X 10.7 Lion and OS X 10.8 Mountain Lion where following a reboot of your Mac Computer, your local Music File Share may no longer be accessible to your Sonos. A subsequent reboot of your Mac or a toggle of File Sharing under System Preferences->Sharing may be required to access your share
Sonos is working to address this problem and provide a fix for this issue.
If you are unable to get file sharing working properly on your OS X Lion or Mountain Lion system and a reboot of toggle of the File Sharing options does not resolve the problem, please contact Sonos Customer Support at one of the contact options available on http://www.sonos.com/support/
We apologize for any inconvenience this issue may cause you.
Sonos Technical Support