This problem has been solved, but I thought I would post it here in case someone else has the same problem.

After I installed SP2, I had sound for everything on my computer except for tv.

I uninstalled the audio driver, restarted Vista, let Vista install it automatically, and we were good to go.

Hope this helps someone.

Had the same issue as well. Removed SP2 and now all is fine. I had this issues with playing recorded HD shows, playing HD channels, and when even trying to play a DVD.

Interesting.  I kept SP2 installed, but it is good to know that is an option in case it comes back.

Same thing happened to me, but the solution was much simpler.

After installing SP2, Vista changed my default audio output to optical. All I had to do was set HDMI as the default under audio properties.

Did you try that before uninstalling and reinstalling everything?

I did change the sound setting back to HDMI since after the SP2 install reboot the sound setting was no longer set to HDMI, but this still did not help. Granted it did allow me to hear wav files (startup/shutdown sounds), but within Media Center I still couldn't hear audio from recorded HDTV shows, live HDTV, or from DVDs.

I didn't try that first, so I have nothing to offer there.

Thanks for this thread. I had the same problem: no sound in Vista Media Center after installing SP2 (the problem affected everything: live tv, recorded TV, and DVDs). The sound otherwise worked fine.

Uninstalling and reinstalling the sound-card driver did not work. Disabling optical output in the sound-card settings did not work.

The only thing that worked was uninstalling SP2. Apparently SP2 does not play nice with Media Center, at least on some systems. Classic Microsoft quality!

Hi,
I have the same problem. After SP2 was installed my media center  did not have sound for DVD's or recorded TV, although I could play mp3 files and movies outside of Media center by stand alone apps like QuickTime, KM player, even Windows media player app worked correctly . BUT there was no sound for DVDs and TV shows within media center.

I tried installing updated audio drivers, making sure that the volume setting within the volume mixer was not muted for any application, none of these fixed the problem.

I had to rollback to Vista SP1 and viola everything worked correctly.

If anyone has any other ideas or suggestion for fixing this problem with SP2 update I would greatly appreciate it
Thanks

Vista sp1 32bit
realtek audi driver version 6.0.1.5548
audio codec ; ALC888S
Directx 10.0

Not exactly the same issue, but this was my SP2 audio tale...

My HTPC with ATI 650 Tuner and ASUS P5Q mobo has both a Realtek 8ch audio system and the Intel A/V HDMI (with Hi-Def audio).

After SP2 was installed, the system would always resort back to the Realtek on startup, forcing me to have to exit MC and change it to the Intel HDMI to get any sound on anything, or doing a second reboot would also smarten it up.
Reinstalling all drivers didn't make any difference.
I finally just went into Device Manager and disabled the Realtek sound device. Now it always defaults to the Intel HDMI Hi-Def on startup.

I seem to be in a similar situation. Vista SP1 w/CableCard, everything was working fine. Realtek HD audio through HDMI (and also were using Creative X-Fi SPDIF output once in a while) was working.

Just installed Vista SP2 and Realtek HD audio HDMI did not work with VMC (TV recordings, live TV). I could hear regular MP3 audio, though. Creative X-Fi SPDIF was working fine when I switched to it.

After much install, uninstall nothing worked. I finally uninstalled RealTek from control panel uninstall program, after rebooting Vista reverted to a vanilla "High Definition Audio Driver" and that seems to be working. Now I have sound on my TV through HDMI with TV recordings and live TV in VMC (w/CableCard).

Good luck to you all. SP2 is messed up (as far as this anyway).

Please see my post here for another simple solution to this problem:

http://www.avsforum.com/avs-vb/showthread.php?t=1153731

Switching HDMI Sound Output from Dolby Digital to Microsoft WMA Pro Audio resolved the issue for me without having to uninstall SP2.

I hope that helps.

rdconway:

Please see my post here for another simple solution to this problem:

http://www.avsforum.com/avs-vb/showthread.php?t=1153731

Switching HDMI Sound Output from Dolby Digital to Microsoft WMA Pro Audio resolved the issue for me without having to uninstall SP2.

I hope that helps.

I installed sp2 again and figured I would give this a try, but no luck. Going back to sp1.

I removed SP2 and all of my issues went away.

There was the audio issue mentioned above; plus after playing a video MC would display the last frame of it and not let me start playing a new video, I would get the new video's audio but a frozen still image of the previous video; and MC would sometime crash after playing a video.
After installing SP2 I even tried reinstalling drivers etc., but the same problems persisted. Remove SP2, everything is back to normal.
My opinion: stay away from SP2. :-)

I received the following support from Microsoft on this and that took care of the problem.

Step 1: Uninstall the sound card driver
==============================
1. Click Start button, type DEVMGMT.MSC in the Search bar, and press Enter.

Note: If UAC (User Account Control) window is prompted for permission to continue, please click Continue.

2. Expand Sound, Video, and game controller category.

3. Right click the current sound card, choose Uninstall.

4. Check delete the driver software for this device.

5. Click OK

Step 2: Reinstall the sound card driver
===========================
Method 1
========
1. Click Start button, type DEVMGMT.MSC in the Search bar, and press Enter.

Note: If UAC (User Account Control) window is prompted for permission to continue, please click Continue.

2. Expand Sound, Video, and game controller category.

3. Double click the audio device we are using.
4. Click Driver tab and click Update Driver button.
5. Click OK.

Method 2
=========
1. Download the sound Driver according to your Sound Card. It’s better to download the latest sound Driver from YOUR COMPUTER SYSTEM MANUFACTURER For example, the HP  website for HP systems is

http://h10025.www1.hp.com/ewfrf/wc/softwareDownloadIndex?softwareitem=pv-58189-1&lc=en&dlc=en&cc=us&product=3629325&os=2093&lang=en

Please Note: The third-party product discussed here is manufactured by a company that is independent of Microsoft. We make no warranty, implied or otherwise, regarding this product's performance or reliability.

2. Install the sound Driver.

Please check if the device works now. If so, our problem is caused by the incompatible driver update.

Does anybody know if MS has a solution to this problem in a future update? I have been unable to solve this with any of the methods listed in this thread. I assume others still have this issue.