Audio Loss in Windows Vista and Win7


Students often ask about an issue where their sound (audio) fails after their Windows Vista (or Win7) computer comes out of sleep (S3) or hibernation mode. Answers were limited on the Internet and with Microsoft and hardware manufacturers so I decided to write an article about it. This problem is common with Windows Vista (and sometimes with Win7) and as far as I have seen could be caused by several different culprits:

Windows update needed: Always make sure that the OS is updated to the latest service pack. This normally takes care of the necessary updates. However, there is an individual update that addresses this exact problem, it can be downloaded from: If the update says “The update does not apply to your system” when you attempt to install it, it probably means that you have SP1 or SP2 installed already, and that this particular update was included in that service pack. Quite often, this update does not fix the problem anyway, and you will more than likely have to move on to one or more of the next items in the list. As of this post, Microsoft doesn’t appear to offer any other solutions or advice on the matter.

Conflicting or faulty speaker connection: Many tower computers have the option to connect the soundcard (integrated or otherwise) to the front panel of the case with a special cable. Depending on the configuration and connection type, this could cause a conflict. There are several things you can look at to fix this:

• First option: Check if the front panel ports are connected to the soundcard (or motherboard) by way of an AC97 cable. Then look for an HD audio cable; most cases built after 2008 will also have an HD audio connector that looks much the same as the AC97 cable. Disconnect the AC97 cable and connect the HD audio cable to the connector on either the soundcard or motherboard (keep in mind that the soundcard will need to be HD compliant). This is a common fix. Both the HD audio and the AC97 cables should be labeled.

• Second option: If your computer doesn’t have an HD audio cable, then remove the front panel cable from inside the PC altogether, then connect the speakers to the back of the PC. Most speakers have a headphone jack, but if you are using a headset, attempt to connect the headphone portion to the speakers, and the microphone portion to the sound card (if the cables will reach in this fashion). The drawback here is that on some systems, a user will only be able to use the headphones or the speakers, not both simultaneously, and the user would have to disconnect the headphone connector when using the speakers.

• Third option: If you always leave the computer in sleep mode and never shut it off, try leaving the front panel cable connected, and connect the speakers to the front panel connector only, bypassing the back connection of the sound card altogether. While this is a noisier option when the speakers are first initialized, it is viable. (Note that this will only work with basic stereo speakers). However, in this scenario some Flash-based audio may cause the audio to fail, requiring the computer to sleep or be restarted to reinitialize the speakers. In addition, complete restarts could cause the audio to fail (although sleep mode doesn’t!) Some people don’t like to use the front panel AC97 connection for sound at all due to the fact that many front panel AC97 cables are not shielded, and as a result pick up noise from other nearby front panel cables like USB, eSATA, etc… But HD audio cables usually do not suffer from this problem, although if you can use an HD cable, see the first option above.

• Fourth option: Purchase new speakers that have an optical connection and connect them to the SPDIF optical port on the PC’s soundcard (if the PC has one). Then connect the headset to the front panel of the PC. In general, optical connections are less noisy, and basically superior connections compared to 1/8″ audio connections.

In addition to these items, always make sure your speakers are connected to a decent surge protector. Some soundcards require grounding which uses a special screw and is grounded by a wire to the chassis of the computer case. And of course, make sure that the soundcard is firmly seated and that any and all connections to the sound card are installed correctly and securely.

Incompatible BIOS, or BIOS misconfiguration: Some systems’ BIOS programs are not compatible with the S3 sleep mode that Vista puts the computer into. A BIOS update might fix this problem, and has been known to work on Sony Vaio laptops among other systems. Also, make sure that the BIOS is enabled for S3 sleep. Incorrect sound driver. Companies like Creative Labs issue new soundcard drivers to combat issues like these. Check if a newer soundcard driver is available, and view the problems the new driver is meant to fix. Watch out for new issues that might occur when installing a new driver (these are usually listed as well). Of course in general it is wise to have the latest drivers for your devices; this includes soundcards, video cards, network cards, chipsets, and so on. Note that a user might need to employ more than one of the options listed above to fix this problem. Also keep in mind that we are talking about S3 sleep here, not S1 sleep. When Vista (or any OS for that matter) attempts to resume from S3 sleep (or hibernation, known as S4), a lot of things happen on the software side, and a lot of devices are re-enabled. Conflicts and errors can result when many processes initiate at the same time.

I hope this helps some of you out there, I know that this is one of the banes of Windows Vista and Windows 7!