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What's DOS?
Posts: 1
Registered: ‎05-22-2010
Location: GZ, China
Message 121 of 125 (3,765 Views)

Re: T400s No Sound

[ Edited ]

I had this problem on W7 X64. Try this:


Press the "volume up" or "volume down" key (left side to the blue ThinkVantage key), and the sound from speaker comes back.


Pressing the "mute" key brings the problem back, and pressing it again doesn't get the sound back. But the "volume up" or "volume down" key helps.


Hope this helps.

moderator note: subject line adjusted

What's DOS?
Posts: 1
Registered: ‎11-05-2010
Location: Mishawaka, IN
Message 122 of 125 (2,630 Views)

Re: T400s No Sound

Pressing the Volume UP or DOWN button next to ThinkVantage button WORKED!!! 
My symptoms were:
T400 Win XP, internal speakers not working, audio jack works, driver seemed ok.
I verified hitting mute did bring problem back which was resolved again by hitting Volume UP or Down.

Thanks again TUCOW

What's DOS?
Posts: 1
Registered: ‎07-14-2011
Location: Seattle
Message 123 of 125 (1,933 Views)

Re: T400s No Sound

Sure it helps, but what is the real problem? Why doesn't the mute button work and is there a real fix?
Paper Tape
Posts: 2
Registered: ‎08-05-2011
Location: Germany
Message 124 of 125 (1,738 Views)

Re: T400s No Sound

Thanks a lot for your help. Now it works perfectly. The only difference on my laptop is that it works even after pressing and repressing the mute button. Perhaps the newest Bios version (1.20) fixed the described bug.

Paper Tape
Posts: 1
Registered: ‎03-08-2015
Location: Canada
Message 125 of 125 (467 Views)

Re: T400s No Sound

[ Edited ]

Hi all, I have been reading this thread for a long time while trying to fix my T400s' sound and I discovered why mine wasn't working, so I wanted to share it with everybody here who's still interested in knowing.



My T400s has no sound from the speaker or audio jack, and static from the microphone. I have installed all supported operating systems: Windows 7, 32/64 bit operating systems, Windows XP, and Vista 32/64bits and tried all avaliable Conexant sound driver versions for each of them and the sound didn't come back. I also tried upgrading the bios to the latest version and since I have no warranty coverage anymore, I took out the speakers and tested them with a multimeter to make sure that it is not blown or melted.



Finally I decided to inspect even closer so I lifted away the black film near the audio jack and I discovered that the sound card is actually fried and full of what looked like "mold", sort of what a leaking battery looks like.


Here is a picture of the "mold" as I found it, you can see that the sound card corner's pins are hidden under a layer of 'mold'.

(sorry for poor quality, that's the best I could do with my cellphone camera)

fried Conexant sound card before cleaning


Here is another picture of the sound card after I tried to gently wipe off the "mold" with isopropyl, you can see the sound card corner's connection pins are all missing.


fried Conexant sound card


Interestingly, the device is shown as working in the device manager.


Sound device is working properly


So this is why my T400s has no sound from the speaker and audio jack. (and a broken microphone.) I now use an external 24bit USB audio sound card for playing/recording sound on this Thinkpad.


Hope you all found this helpful!


Lenovos and Thinkpads owned:
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