The Audio worked on my Thinkstation for several days and then stopped working, perhaps related to installation of some additional hardware and software, notably a Plantronics headset which came with software and an audio driver called SAVI OFFICE to link the headset to your media player.
Uninstalled reinstalled drivers both by Windows 7 troubleshooter and Manually.
Uninstalled and downloaded latest drivers from Lenovo download center and reinstalled.
Installed in compatibilty mode back to XP.
Even the the Windows HD audio Device doesn't work.
Checked Bios sound is Enabled
Windows says all the latest drivers are installed but no audio device is installed it says code (39) problem with driver.
Lenovo has replaced some hardware, so it seems to be a software issue. How to resolve?
Code 39 is a device driver, registry error. It usualy is caused by installing or uninstalling a program like antivirus software or installing the wrong device driver and it corrupts the registry.
You want to make sure you install drivers from the Lenovo Site because many are tailored specifically for your machine. You may want to try deleting the upper and lower filters in the registry. You can use the link as a guide. In this case, it may be the lower filters.