Audio in/out ports on Thinkpad Mini Dock Plus Series 3 with W520 inactive

[Stique]

I have 3 W520 laptops and 3 Thinkpad Mini Dock Plus Series 3 docks. The audio 1/8" audio out and microphone ports are not detected by Windows. In sound settings, the High Definition Audio Device is always disconnected. I read that there was an issue with background audio through the audio ports on an earlier run of these docks, but the production date on these are all 11/07 (after Lenovo fixed the problem). Has anyone had a similar problem? Are the ports inactive for the W520 by design?

[Stique · Accepted solution]

Solution: ...drivers. Should have checked this first. I figured our support desk would have done this. I figured wrong.

[jrainey]

I just connected speakers to the ports on my W520 Dock..  I get a high pitched noise through the speakers, weven when turned down.  Do you know what the issue was with the previous docks?