HTPC GURU help needed

[mmatheny]

OK, Frys had a sale on an LG Blu-Ray/HD-DVD/DVD/DV burner for $89. So I sprung on it. Also got a DVI to HDMI cable so I can see HD in all it's wonderful glory.

So, I install the drive, load all the software, bring it down to the TV, and when I tried to play an HD-DVD movie I also picked up, I got an error about HDCP. Well, the video card was a 7900GS, and I don't think it supports HDCP, so I swapped with the 9600GT in my main machine, fired it up, loaded the latest drivers, and was actually able to WATCH HD - notice I said WATCH! After I installed the latest drivers, nVidia decided since I had an HDMI connection, it wanted to transfer audio through that device, and since DVI doesn't support audio, I now have no audio!! How can I tell the driver that I DON'T WANT AUDIO via the DVU-HDMI cable, and to start letting the audio port on the back of the motherboard output audio??

I ran across this hack (can't believe it's not just a simple switch in the software), but I thought I'd post to see if someone else has a more sane way of accomplishing this.

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*** WORKAROUND FOUND ***

There's a way you can configure the NVidia driver (prior to installing it) to override/ignore that it 'discovers' an HDMI connection, and thus NOT send the digital audio signal through the DVI connector (obviously requires that you can and DO use an external analog audio cable). This solves the problem for those of us with [COLOR=green! important][COLOR=green! important]HDTV's[/COLOR][/COLOR] that auto-sense HDMI/analog audio (mine's an Olevia 237T) and have nVidia graphics (mine's an HTPC based on a 7100/630i motherboard w/integrated graphics). I found this originally at http://forums.nvidia.com/index.php?s...=&#entry330319 - although it was being used for a different purpose - but I can certainly vouch that it works!

Here are the steps in full (rewritten by me)... You need to have your PC hooked up to your TV, so the EDID discoverer can get your display's ID code:

1. Get Phoenix EDID Designer, (http://www.tucows.com/preview/329441), [COLOR=green! important][COLOR=green! important]unzip[/COLOR][/COLOR] and run the exe (no install reqd)
2. Click Tools->Extract registry EDID, then double click the line for your TV/monitor in the popup
3. Click Tools->Byte viewer, and note down the values in row 00, columns 08-0B (4 bytes)
4. Start the installation of the latest Nvidia drivers and cancel out once the files are extracted
6. Open the file "nv_disp.inf" in a text editor. By default for the current drivers this is in C:\NVIDIA\...\169.21
7. Scroll down to the section [nv_SoftwareDeviceSettings], add the following line there, replacing the "XX" values below with the 4 values noted in step 3:

HKR,, OverrideEdidFlags0, %REG_BINARY%, XX,XX,XX,XX,00,00,FF,FF,04,00,00,00,7E,01,00

(In my case the TV code was SYN 0043, the four values being: 4F,2E,43,00 )

4. Uninstall your current drivers and reboot
5. Install the modified drivers by running the previously extracted setup.exe. By default for the current drivers, this is in C:\NVIDIA\...\169.21. You'll get a warning about the driver not being signed because of the modified inf. Just press OK.

Reboot, and you should have GLORIOUS AUDIO!!!
==========================================

[mmatheny]

Well, seems my TV is refusing to receive audio in on the RCA jacks for the HDMI port that supports DVI conversion! I take a tape recorder and hook it to the audio inputs, and nothing. Hook it to another input, I get sound. The manual does not state anything about telling the port to receive audio over the HDMI or analog inputs!

[mmatheny]

Well, put my 7900GS back in and vilola! Have sound through the analog ports for HDMI2 - so, what is going on here, and how can I fix it? I might try the fix I posted first. But, there should be a simple switch (analog or digital sound output!!)

[martint123]

You seem to be a glutton for punishement no matter what you try

[mmatheny]

Seems as if the TV is at fault - if it sees an HDCP compliant input, it disables the analog inputs and expects audio on the HDMI interface. Funny thing is, there is ABSOLUTELY nothing in the manual that even hints as to this being the case. Here's all it says about connecting a PC via DVI-HDMI cable:

Connecting a PC
Using the HDMI/DVI Cable

1. Connect a HDMI/DVI cable
between the HDMI IN 2 jack
on the TV and the PC output
jack on your computer.

2. Connect a 3.5 mm Stereo plug
to 2RCA cable between the
DVI IN (HDMI2) [R-AUDIO-L]
jack on the TV and the Audio
Out jack of the sound card on
your computer.

[pBS]

i have one of those Olevia tvs that does that, but mine seems smart about it..
i have only 1 hdmi input so i had to get a switchbox...now the tricky part..
2 of my hdmi sources have audio built in, 1 doesn't...

but it handles it perfectly! even tho the hdmi sources get switched externally, it 'senses' when there's audio on my analog inputs or hdmi input and uses the one that's outputting audio..
so my tv connection analog audio w/hdmi vid works, and the hdmi vid+audio too..
i had to set my tv to autodetect hdmi audio in tv menus tho..
that way it senses if the audio is analog or digital..
only 'bug' so far is when changing hdmi sources on the switch sometimes when audio is muted completely it doesn't sense any audio, but i just switch inputs and back and it fixes it..

oh and there's also the selection of default sound device in control panel, may want to try checking 'only use default device for audio'
or something like that in the audio page..[locks all sound to a certain sound card]

[mmatheny]

Well, maybe it's the video driver turning off analog out on the motherboard - I will hook speakers directly to it to test.

[dennit]

Seems as if the TV is at fault - if it sees an HDCP compliant input, it disables the analog inputs and expects audio on the HDMI interface. Funny thing is, there is ABSOLUTELY nothing in the manual that even hints as to this being the case. Here's all it says about connecting a PC via DVI-HDMI cable:

Connecting a PC
Using the HDMI/DVI Cable

1. Connect a HDMI/DVI cable
between the HDMI IN 2 jack
on the TV and the PC output
jack on your computer.

2. Connect a 3.5 mm Stereo plug
to 2RCA cable between the
DVI IN (HDMI2) [R-AUDIO-L]
jack on the TV and the Audio
Out jack of the sound card on
your computer.

You do seem to be a glutton for punishment!
The TV instructions look a lot like those for a Samsung 650 where PC input is on HDMI2. You haven't said, but if you're using a Samsung 650/750 then go into the menu and rename the HDMI2 input to "PC." Until you do that, it expects audio on HDMI, not the analog audio input.

[mmatheny]

It IS named PC - and it is a PN50A550. (but will change and then change back to see if it makes any difference) And I also confirmed, it IS the TV - the analog is still coming out of the PC.

[mmatheny]

OK - changed it to something else, then changed it back to PC = still refuses to accept audio on the analog jacks - confirmed the PC is outputting by plugging audio into another analog audio input and changing to that source.