pantherts

Hi everyone,

Being that this if my first post I just want to thank everyone that has contributed to the KX project and have been enjoying it for quite some time now. I have been trolling the forums as well for a long time as well. Now, on to my issue.

I currently am running the latest KX driver (3545b) on a Sound Blaster Audigy 2 ZS (Just the regular edition not Platinum) and have done a fresh install of it numerous times (the DSP is unmodified). I have a coaxial cable hooked up to my SPDIF port with the proper connector and have gotten the passthrough for MediaPlayerClassic to work with DVD AC-3 and DTS when using the Creative drivers in the past. I cannot seem to figure out how to get this to work in KX.

I have studied all the inputs and outputs and have noted how the main mixer controls work. I understand the SPDIF selection on the mixer main page and I have tried enabling/disabling different options here. I do know my way around the DSP and have been experimenting with the hookups for a while. I just can't seem to get anything to actually passthru using the AC3 passthru feature of KX. The AC-3 Passthru icon shows up in the bottom right of my screen when I play a DVD using MPC's own internal AC3 to SPDIF filter, so I know it's hitting KX but I'm not getting any sound and the receiver is not detecting a DDigital signal coming into it. I've tried playing through all of the KXWave devices and have not found sound to come out on any of them using this configuration. Am I missing something here? Thank in advance to anyone who can shed some light on this.

BTW: Currently I have SPDIF 0 selected for AC-3 passthru and right now of course the standard two analog channels come through to the amp fine. But when I play a digital stream to the KX drivers (AC-3 stream driected to SPDIF) there is no sound whatsoever.

Maddogg6

does stereo work?

Have you identified what SPDIF out you are connected to?

pantherts

Yes the stereo works while playing something like winamp it does come out to the receiver through the spdif fine. It's using SPDIF 0.

Russ

AFAIK, it should just be a matter of selecting "SPDIF 0" in the "Toggle 'AC-3 Passthru' mode" combo box.

Beyond the above, make sure that "Toggle 'S/PDIF Bypass' mode" is not enabled.

pantherts

Yeah, that's what I thought as well. I'm not sure why it's not coming through correctly. I'll try to give you some more information of what my setup is currently after driver install.

On the mixer page the switch from front to back is checked because this this card has both the IS2 and the 10k2. I have my headphones plugged into the back of the computer in the rear channel port. Control panel shows the default sound device to be KXWave SB0350 10k2 [b400] 0/1. When I play a song through winamp I can hear the song in stereo coming out of my receiver due to the SPDIF being plugged in. When I play a DVD on the computer and direct the sound to SPDIF (I'm not positive which output device to select in the player software for this setup though it seems i've tried them all) with output device KXWave 0/1 selected, the AC3-Passthru icon shows up and any other sound i had going on the computer stops playing. I'm guessing the reason for this is because the SPDIF and main left/right sound are both going through the same lines here, 0/1.

Another thought came to mind when I noticed that in MPC, AC3 can be sent as PCM 16, PCM 24, PCM 32, and IEEE Float. Could this be an issue perhaps? I also have tried passing the AC3 signal through FFDSHOW and AC3 Filter to see if that made a difference. It did not. Every piece of software hits KX and the AC3-Passthru icon shows up but no sound is coming out when using a pre-encoded digital source.

Russ

I do not know if I can answer all your questions as I do not have an external receiver/decoder to test with, but I will answer what I can.

I do not *think* that this option should effect AC3 passthru.

The device has to be Wave 0/1.

I am not sure why other sounds would stop playing (you should still be able to hear the other sounds in your headphones).

This should not make a difference with AC-3 passthru, as (AFAIK) it should pass the signal as it is (unaltered).

Russ

BTW: To try and rule out potential issues with the MPC configuration (which can be rather confusing), and the configuration of DirectShow filters, etc, I suggest trying VLC using it's "A/52 over S/PDIF" setting.

Also, here is an audio file that you can use for testing.

pantherts

Russ, thanks for the tips. I will give it a shot when I get home from work today and see if I can get some sound coming out of this setup. I did try to bypass MPC's internal filter again last night with FFDSHOW and took a look at the output in FFDSHOW's Audio Decoder settings. This is what happens when using that setup. I go to the Output section in the FFDSHOW audio decoder window. At this time a stereo version of the AC3 file is coming out of the receiver through spdif. As soon as I check the AC3 passthru box inside FFDSHOW the sound stops, the AC3 Passthru icon from KX comes up, and the receiver doesn't show any digital source is being fed to it.

To make it easier, here is my complete setup in images:

http://www.shadowhunt.com/images/DH/SoundSetup1.JPG
http://www.shadowhunt.com/images/DH/SoundSetup2.JPG
http://www.shadowhunt.com/images/DH/SoundSetup3.JPG
http://www.shadowhunt.com/images/DH/SoundSetup4.JPG
http://www.shadowhunt.com/images/DH/SoundSetup5.JPG
http://www.shadowhunt.com/images/DH/SoundSetup6.JPG
http://www.shadowhunt.com/images/DH/SoundSetup7.JPG
http://www.shadowhunt.com/images/DH/SoundSetup8.JPG
http://www.shadowhunt.com/images/DH/SoundSetup9.JPG
http://www.shadowhunt.com/images/DH/SoundSetup10.JPG

Thanks Russ and MD for the quick responses!

Russ

Everything there looks OK to me.

If you disable AC-3 Passthru in kxmixer, does kX decode it?

Are you sure that you did not change anything on your receiver?

BTW: What OS are you using?

pantherts

Russ, thanks again for the quick reply. I'm using Windows XP SP3. As far as the receiver goes, everything should be fine on there since stereo makes it there fine through the coaxial. The amp reads that it is a digital connection coming through because of how it's hooked up (As opposed to analog connectors). The only thing it's not doing is switching from Dolby ProLogic II to Dolby Digital when the AC3 source is coming in. Perhaps the next step here is to try and install the Creative drivers to make sure nothing has changed on the Receiver end?

Maddogg6

@Russ: Would setting SPDIF out freq affect passthru?
Perhaps setting to 96000 would help... ??

Russ

I do not know, again I do not have a receiver to test with, but I do not think that it makes any difference. I played around with it a little myself, changing the frequency settings while watching the status screen, and it always auto-switched to 48000 to match the AC3 stream.

That is what I was wondering about, does it normally auto-detect an AC3 stream, and auto decode it? Is there some setting on your receiver that might effect that?

Of course if your could verify that your receiver still works with other AC3 sources (whether you install the CL driver, or connect a DVD player to it, etc) it would be good.

pantherts

Okay, here's what I've done. I switched off the SPDIF passthru setting in KX and guess what happened. BSOD in KX.SYS! To answer your question Russ, yes my receiver is actually hooked up to two other devices that output digital; a dvd player and another computer with a DVD decoder card that outputs ac3 and dts as well. Both of these work fine and the receiver auto switches from Dolby ProLogic II to Dolby Digital and DTS. So there is no setting to specify on the receiver since it auto switches.

Russ

Err, yeah I forgot about that. The kX decoder does that sometimes (though for me it usually only happens when decoding from SPDIF IN), so you might not want to test that (again).

pantherts

Haha, yeah that's what I was thinking. I don't think I will be doing that again. Anyways, I'm not sure what could be happening here. It seems the KX driver is sending out a digital signal, or modifying the one that is going out in someway, that the receiver doesn't recognize. Is there any way to see the exact signal that is passing through the KX driver while the source is playing?

pantherts

Maddogg: By the way, I tried switching the SPDIF output freq. to 96000 and my amp immediately detects that I have done so by stating "96 KHZ" on the screen. When I begin playing back an ac3 source on the computer the receiver seems to switch back to the 48 KHZ setting automatically until the source is stopped. At that point it immediately switched back to saying 96 KHZ. So it seems to correctly identify the source that is coming into it but it's just not "agreeing" with the digital source it's getting, no matter what the frequency.

Russ

No, it bypasses the DSP, so there is not really any way to get a look at it (at least not that I know of).

BTW: I do not have an A2ZS, and things are a little different with my card regarding digital output, so I cannot be sure of the specifics with your card.

Are you sure you are getting a signal from the card, when using AC3 passhtru?

I do not think the swap front and rear option should effect AC3 passthru (based on how it appears to work with my card), but I cannot be sure that is the case with your card, so you might want to uncheck that option and test again (if you have not already tried that (although I think you probably have)), just in case. I would also try each of the 3 SPDIF outputs in the AC3 passthru combo box, with swap front and rear disabled. (I know it works with regular PCM signals with SPDIF 0, but swapping front and rear might act differently with that).

With my card, I can connect digital out to the coaxial input on my Audigy drive, and use that to verify which setting outputs a signal, etc (using a peak plugin on the input in the DSP to look for the signal, etc), I do not know if you are able to do something similar with your card (maybe use the CD_SPDIF header), or if you have some other way to verify that you are outputting a signal, etc).

I not sure what else you you do. Although I do not have a receiver to test it with myself, I am fairly certain it works (people seem to use redocneXk with it OK). I wonder if maybe there is an issue with kX and your particular receiver (it seems doubtful, but I do seem to recall a post ages ago from Eugene about adding a fix to get it working with certain receivers, so...).

pantherts

Russ,

Yes I have tried each of the SPDIF settings and I also wanted to acknowledge your previous post regarding VLC Player and using it's SPDIF output functionality. I installed VLC and set it up to output on KXWave 0/1 using SPDIF and still no go. Now here's the kicker regarding your statement with redocneXK, I have gotten this to work with KX before. Yes. I have gotten redconeXk to work properly with my 5.1 surround games and the digital signal is detected. I havent tried it as of late though. As for the front to rear swap switch, I am in the process of testing this now.

I have not changed anything except for the KX driver version since I last did this but I also cannot for certain verify that regular ac3 and dts was ever working in the KX driver for me. With redconeXk it was though. Does this help at all? Could it be the version I have of KX has a bug? I will also do a forum search regarding the receiver fix to see if anything comes up.

Russ

If it did work with redocneXk, then I would doubt that it is any compatibility issue with the receiver. I suppose there could be an issue with 3545b, but I would think that there would have been more people complaining about it by now, if that were the case.

BTW: There is a setting for the number of AC3 buffers under kX Settings. You might try different settings there to see if it makes any difference.

pantherts

I would think so too, I just tried running redcneXk again (after hooking up the ASIO ports in the DSP of course) and still no digital light. Perhaps I will uninstall this version and head back to a previous version to verify that it isn't a bug. I believe you are right though, that more people would be complaining about it. I'll let you know what happens.

pantherts

Okay, some good news and some bad news. I have confirmed this setup works correctly in KX version 3541. Digital output works flawlessly in both MediaPlayerClassic and VLC player using the KXWave 0/1 device and sending the stream to SPDIF. I have tested MPC using FFDSHOW and the internal source filters sending the signal to the SPDIF. 3541 works perfect. I will step up and test 3544a next to see if something broke between the alpha and beta. (The bad news was that this is a driver bug, whereas the good news was that we finally figured this whole thing out!)

pantherts

Okay I tested 3544a and it does not work properly either with the Audigy 2 ZS for SPDIF output of AC3. Any other versions I should be testing here?

Russ

No, I do not think you need to test more versions. Hopefully other people can verify this, but I would post a bug report in the 3545 bug reports thread with a link to this thread.

pantherts

Okay I have submitted the bug report to the 3545 thread. If anyone else that has been following this thread happens to have an Audigy 2 ZS and is using an external receiver could please test that their AC3 passthru is/isn't working, I would appreciate it.

Thanks Russ and Maddogg for all your assistance regarding this issue! You both have been very helpful in helping me diagnose this problem.

Russ

Your welcome

BTW: You might want to edit your bug report and just add that you are using WinXP (so E. does not have to dig through this thread to find out what OS you are using).

pantherts

Done. Thanks, Russ!

Clayman1979

This bug is still there, I mean version 3550.
Created separated topic in "In Russian":
Проблема с SPDIF passthru

skunobe

Yes, I have the same issue. I tested 3544a, 3545b, 3550 and 3541. Only 3541 is working. All the other versions show Pass-through pop-up window, but there is no AC3 signal can be detected by Receiver, instead, it still display PCM signal from sound card. I have tried SB0240, SB0350 and SB0090, all the same.

My OS is Win XP+SP3. Now I'm sure this is a bug even in the latest version.

m4n1ak

Same problem

In driver ver. 3550 doesn't work "ac3 passtrough" mode.


Sound card: Audigy 2ZS (sb0350)
Receiver: Yamaha RX V357
OC: Win 7 (32bit)
Player: Media Player Classic + AC3 Filter (otions: As Is + Use Spdif)

With 3550 my receiver displays "Unknown Digital" instead of "Dolby" and there are no sound.
But, with 3539 and same config (simply reinstall driver and select "Master mixer" instead "AC3/Spdif". Other settings are the same i.e player config, AC3Filer settings, same settings for kx [samplerate,ac3 settings, etc]) ALL Works FINE!!!

3539 good, but i need ASIO, that works normally under Win 7 only with 3550

juninho85

i've same problem,but with a onkyo 608 as amp,i've tred 3550 and 3551 alpha but ac3 passtru not work!
someone has solved somehow??