The speakers working only intermittently could be a hardware problem. I would suspect a faulty sense pin in the headphone jack. This will allow external speakers to work and also the speakers will work when tested, but not otherwise. If this is the case then Dell will fix it under the warranty, but they might not if the current OS is different from the one they pre-installed.
A possible explanation for this combination of symptoms:
* Speakers don't work and are not muted or deselected
* Headphone jack does work
* Reinstalling audio driver does not help
* Audio test in Dell Diagnostics passes
* On models with 2 headphone jacks, one may be "checked" in the control panel as if in use
The Dell laptops with 92HD audio utilize IDT's Universal Jacks technology, which is somewhat complicated. In addition to the usual mechanical parts, the jack also uses current & impedance-sensing techniques to trigger software configuration and switching (to send the audio signal to the speakers). So there are three areas of potential failure: mechanical, electronic, and software. Sometimes, a little very gentle wiggle of a plug in the jack will get it to resume normal functioning, at least temporarily. There is a sensing pin in the jack (Sense_A pin) that is used to detect the presence of plugs and it can be the cause of failure to trigger the software switching. Failure of the sense pin usually results in the computer behaving like there is always a plug in the jack.
Normally the audio test in Dell Diagnostics would confirm that there is a hardware problem, but the Universal Jacks can cause a false result in Diagnostics. That is because Diagnostics operates in DOS, outside of Windows, so a Windows software misconfiguration is irrelevant to the test even though in this case it is caused by hardware. So the audio test can pass in Diagnostics, correctly signaling that software configuration is the immediate cause of the problem, but missing that a hardware problem, the bad jack or sensing pin, is the root cause. In these instances the only reliable diagnostic procedures are to try a new motherboard or to use PC Restore (called Factory Image Restore in Vista) to restore the computer to its original configuration as shipped from the factory. If the speakers still don't work after PC/Factory Image Restore then there is definitely a hardware problem even if it passes the normally infallible Dell Diagnostic audio test.
I have exactly the same symptoms for my Dell Studio XPS 1640. I upgraded to Windows 7 64 bit around December last year (2009). The problem with the audio started soon after that. I've been searching the internet for any postings about this and I've come into this and another one (http://forum.notebookreview.com/showthread.php?t=427644). How prevalent is this problem with this systems?
"How prevalent is this problem with this systems?"
It depends on what exactly the problem is. If it is the failure of the sense pin as I described then I don't think it is especially worse on the Studio XPS 1640 than any other model. I discovered the problem soon after Dell started implementing HD audio with re-configurable jacks. Since then I have posted about it maybe once a month. It started with the earliest model that had these, the Inspiron 9400, and has probably occurred in every model since. So the problem is across all model lines but probably only a small percentage of them. Of course it was the same before re-configurable jacks. A certain percentage of the simple spring leaf jacks failed too.
I'm having a very similar issue with my XPS 1645. It's hair-pulling frustrating. Basically it's about a 50-50 chance that my audio will lock-up or not. Usually what happens is, I'll try to open Itunes and it won't work, so go over to the volume adjustment icon in hte systray (Windows 7) and move the slider and oh...it locks up.
Basically anything that tries to use the audio crashes, including the volume control, it will crash the browser, itunes, video players, whatever touches the sound and all at random. I usually have to try a few restarts in order to get it to work again. I even tried updating the drivers, but the install kept crashing...arrgh!
Anyone had any success with the crashing portion of it all?
Dell XPS 1645, same issue here. I can already tell when no login sound is played that i can as well just reboot again because everything trying to play sound will lock up! Dell Support told me that i'm the only one having this problem. Now it's a least two? Or more?
I have this issue too!! At first I thought my Win7 Upgrade went bad somehow. So I clean installed. At the very end, thinking I solved the problem, BAM it happens again. Then it hits me, it must be a driver issue.
The driver dell provides obviously has this fault. IDT needs to fix it, but IDT won't deal with end-users. Only the OEM.
What we need to do is pick a day that we ALL call dell complaining of this same problem. One after another, asking to esclate again and again until we get to someone who can contact IDT and get us a fix.
P.S. I discovered another problem like this ... with the Dell Touchpad Driver. If you plug in a USB mouse, it will disable the touchpad no matter what the setting is. Also, hte scroll settings won't even load. Solution? Uninstall Dell Touchpad Driver.... and google "synaptics 220.127.116.11 driver". That driver will solve the problem, and even give you more features like multi-touch!!!!
Shame on you Dell for not providing your customers updates regularly, NOR even when there are obvious driver problems.