Windows 7: HDMI sound output problems

I am astonished by how primitive the Windows 7 sound system is.

The setup:
An HDMI cable connects a Radeon HD 6870 to my Samsung TV.
I use the TV for both video and audio output.

Windows seems to detect whether the output device supports audio and how many audio channels it has. The problem is, it does that in a very unwise way.



If I turn my TV on, and then start Windows, things work fine.

Now, if I start Windows, and THEN turn my TV on, I get no audio. The only "fix" is to logoff and login again so that it re-checks the TV (now turned on), and sees it supports stereo audio output.

Even worse: if I turn my TV on, start Windows and for some reason turn the TV off, the sound gets disabled as well!

I have never seen a problem like this surface from the order of turning things on.

Sometimes I like to plug my PC into my Blu-Ray Home Theater. The wiring is very similar:
HDMI cable from the Radeon into a Sony BDV-E280 Home Theater.

It supports 5.1 audio. My card supports up to 7.1 channels output through HDMI, and I have tested two different HDMI cables.

However, added to the previously specified audio problems, for some reason Windows thinks the output source (the 5.1 home theater) has only two channels, so all I get is STEREO.

I have tried updating drivers, even downloading different drivers, searching for some hacks that could solve it at all...

I found a thread once of a guy who had the exact same problem and got it to work on Linux with some fancy console code.

Given this is primary an OS issue, the solution would be to force Windows 7 to output all the 6 channels uninterruptedly.

Any Windows 7 experts or hackers could give me a lift on this?

Thanks.

Just to add to the drama: today I left my TV on the whole evening, uselessly wasting its capacitors and shortening the screen lifetime, while I was out so that I wouldn't have to deal with the sound problem when I get back home.

That's a major OS design flaw and I haven't seen anyone that had any of these problems ever finding a solution.
Your help may help many others as well.

Thanks!

By specification, HDMI is two channel audio. If you want more, you need to use S/PDIF out and a decoder capable audio device. Some devices with HDMI input "fudge" the extra channels by delay or frequency changes but PC HDMI output is Stereo. It has nothing to do with the OS. If your PC audio output device and drivers will allow it, you can get up to a combined 10.1 channels through the output jacks on most PCs. Even with Windows.

As for your sound disappearing, it could be that you have selected the display device to be the default audio output. If you disable the device, Windows will disable the output since it no longer exists. You should review your setup and determine the best options for your needs but I would suggest that you change the default output to the system speakers. When you want the video device (TV) to be the primary audio output device, change it back. It takes all of one right click and a few left clicks to accomplish this.

Hello carwiz!

Strangely enough, if I play a movie (say, from a DVD) with 5.1 audio on Windows Media Player it outputs all 6 channels to the home theater. I think we can safely assume that my hardware does supports surround sound, so the problem must be caused by faulty software (which I think has to do with the Windows sound system).

I guess it works on WMP because of some specific configuration of the player that overrides the system audio output.
The problem is, I want not only to watch movies but also to play games and use sound editing software with surround sound, and they fail to detect my surround system if the OS wrongly specifies my output as STEREO.

As for the other problem, let me illustrate what goes on

This is my system working as it should:


Then I turn my TV off/on (it's instantaneous, notice the difference of 1 minute in the clock) and my HDMI Output gets permanently disabled until I go to the logon screen or reboot.

(on a side note: the default "Digital Audio (HDMI)" never worked for me, so I just disabled it)

I don't use speakers, there's nothing connected to the mobo 3.5mm jack. My primary and only sound device is my TV through a HDMI cable.

Thanks.

I have a Zotac ZBox PC with an AMD fusion e-350 processor hooked up to a tv via hdmi. This same problem just started happening to me recently - I have to sign off and log back in to fix the audio every time the tv shuts off. I think it started with the Catalyst Control Center 12.3 update about a week ago, but it's unclear because I also installed a bunch of windows updates then too. Catalyst 12.4 is out now, I'll let you know how that goes.

Hello! I too have catalyst. I updated it as well and the problem still occurs.

Could it be it's being caused by amd drivers?

I don't know whether the problem is due to AMD drivers or Windows itself. I've also seen people blame the "hdmi handshake" from the TV itself, but because this is a new problem to me, I don't believe it's the TV's fault. I'll try to restore a System Restore point from last month tonight. Upgrading to Catalyst 12.4 made no difference. I didn't see any options in the BIOS related to HDMI audio.

If that doesn't work, then I'm going to use this as an excuse to purchase a digital audio receiver and some speakers and just use the SPDIF connection. But I *really* wish I could get this fixed.

I restored a May 8th system restore point and now hdmi audio works fine again for me. I'll try updates a little at a time over the next few days. I'm running Catalyst 12.3 now, which is the same as when i was having the problem, so I now believe this is a Windows Update problem.

Thanks for the testing. I'd love to hear from you when you find out what caused this problem.
Also, glad to hear it's not an AMD driver problem.

This is the exact same problem I have