No speaker sound - only headphones...

[andyoxon]

Any ideas?  The headphones work fine, but when one removes the jack - nothing.  The PC speakers don't appear to muted anywhere, AFAICS.  I have shutdown and re-booted too.

[Jaded]

Something physical to do with the headphone jack? I think the speaker sound is cut out by a switch activated when you plug the headphones in.

[Feanor]

It depends.

Are you talking about a laptop with built-in 2-channel speakers?
If so, then as Jaded says, it's a mechanical contact in the 3.5mm Jack socket that opens when you shove in the headphones. Un-plugging the 'phones should allow the contacts to spring closed, and the speakers should workee again.   If not, then the contacts need a bit of jiggling / cleaning.  Try some plugging / un-plugging cycles.

If it's a desktop machine with a fancier multi-channel sound hardware, it may be more complicated. The headphone jack on the front of the PC may be a seperate output from the sound hardware in addition to the array of jacks on the back, where the speakers plug in.   For example, on my system here, it's got 7.1 channel speakers plugged in the back.   If I plug headphones in the front, the Realtek HD Audio driver detects this and asks 'Hey, was that headphones you just plugged in?' I say 'yes', and in mutes the rear outputs and down-mixes the 7.1 to 2-channel for the phones.

So in this case, it's not a simple dumb mechanical thing, software is involved.

[andyoxon]

Thanks Jaded/Feanor,

I've not looked at the anatomy of a socket before...  could be this.  I've tried putting the jack in and out


edit - looking into the socket and the next to microphone socket I can see that the brass tab in headphone socket is not as far into the centre of the socket, as the microphone 'tab'.  Don't really want to poke around in the socket though.

The machine is a Dell 9400, and it has speakers on top surface and a subwoofer underneath http://www.notebookreview.com/default.asp?newsID=3379 (not exactly the same spec as the review model)

Running sigmatel audio software...

[plum]

edit - looking into the socket and the next to microphone socket I can see that the brass tab in headphone socket is not as far into the centre of the socket, as the microphone 'tab'.  Don't really want to poke around in the socket though.

If I understand that right that's just the difference between mono and stereo, there is a second one in the headphone socket out of sight. Look at the headphone plug you can see it's divided into three parts, l/r/ground. The Mike only has two so the connector can be placed more centrally..

[Feanor]

The fact that there's a subwoofer involved suggests it may be more that dumb mechanical switching, since the sub-woofer will need muting too ( assuming the sub-woofer is not just wired directly off the L+R speakers in some way,and it really is a seperate LFE channel from the sound hardware.

Have a poke around in the sigmatel software.
Does it have the ability to detect when things get plugged in?
If so, then the software is certainly playing a part.
Also if so, does it still think the 'phones are plugged in?
In which case, we're back at the contacts on the socket again ( in the software-controlled scenario, the socket contacts don't directly switch the audio; rather they send a signal to the software to mute the speakers etc. )

ETA:  What OS is on it?  Using win7 as an example: go into the Control Panel, 'Sound' option, 'playback' tab and see if the speakers and 'phones are listed as seperate devices, and ensure your speakers are set as the 'default' device.

[andyoxon]

I was hoping the speaker mute may have been checked, but it's not.

Looks like the socket to me. 

[Biggsy]

I've never had a 3.5mm jack socket fail in the way suggested in my 30 years of experience of using and bodging 3.5mm jacks.  I've had every other failure imaginable with them, but not that - so I think it's unlikely.  Also it won't incorporate a speaker switch anyway if it's a line-out rather than headphone socket.  (My DELL lappy has both).

But unlikely things do happen!

[andyoxon]

Thanks.  I could try and re-install the sigmatel driver?

[mcshroom]

Probably done already, but sometimes my sound card packs up completely on my netbook and required a reboot. Then it works fine

[andyoxon]

Yes I'd rebooted.  Normally fixes things most things.  Also reinstalled driver now too.

I think it is a physical thing with the socket.  The screen shots above seem to show that it's either headphones or speakers controlled by the jack going in or out...    Time for some external speakers possibly.  I suppose I could open the machine up and tweak the contacts or summat, but I probably make things worse...

[Feanor]

That all looks as expected.

I have a HP laptop here with a different HD codec, but it looks much the same as yours.
I did notice on mine, that the Jack Information icon is not solid black, but has a lighter grey circular border.   I thought this might change to solid black as I plugged in headphones, but it did not on my machine.   However, on yours it may signify it thinks it is plugged in.

If you r-click the Speakers / Headphones, there's an option to 'Configure Speakers', make sure its all OK in there too.
Also use the 'test' option.
Do you get the notes playing in the phones, but not on the spkrs still?

[andyoxon]

That all looks as expected.

I have a HP laptop here with a different HD codec, but it looks much the same as yours.
I did notice on mine, that the Jack Information icon is not solid black, but has a lighter grey circular border.   I thought this might change to solid black as I plugged in headphones, but it did not on my machine.   However, on yours it may signify it thinks it is plugged in.

If you r-click the Speakers / Headphones, there's an option to 'Configure Speakers', make sure its all OK in there too.
Also use the 'test' option.
Do you get the notes playing in the phones, but not on the spkrs still?

If I configure I get notes in the heaphones, but nothing when they're unplugged...

[Valiant]

Sounds to me like the actual "dumb" switch has failed. Happened to me once on my powerbook. Thankfully a bit of switchcleaner and multiple connections and jiggling about got it back to normal. I'm guessing it's was dirt and dust clogged it up.

[andyoxon]

Sounds to me like the actual "dumb" switch has failed. Happened to me once on my powerbook. Thankfully a bit of switchcleaner and multiple connections and jiggling about got it back to normal. I'm guessing it's was dirt and dust clogged it up.

how did you apply the switchcleaner? 

[Valiant]

Just sprayed it in from the outside lol

[Wonky]

Servisol switch cleaner and lubricant is fantastic stuff.
Spray it in to your chosen electromechanical switch and exercise.
It will free up a fruit machine button that has been stuck with dried beer, and we use it on airplanes at work. Magic stuff. No need to deactivate your equipment either.