Multi-channel LPCM through HDMI

James Strachan

Newbie Location: United Kingdom Joined: May 22, 2014 05:27 Messages: 3 Offline

Solved by

May 22, 2014 05:41

No luck last time so I will try again and see if any of the resident geniuses can perhaps point me in the right direction.

When playing Pure Audio Blu-ray discs with multi-channel LPCM audio tracks through an A/V receiver that supports HDMI 1.4 (with HDMI 1.4 cables) PowerDVD 14 will only output 2 channels of LPCM. And it does not seem to be downmixed to stereo: the other channels are simply missing.
With PowerDVD 13 on a different PC through s/pdif there was an option to convert LPCM to DTS or Dolby Digital but that option is no longer there in PowerDVD 14, which means I cannot play these discs through HDMI.
So I tried playing some 6 channel LPCM audio tracks using Foobar2000 and it can play all 6 channels perfectly, which seems to prove that it is PowerDVD 14 that is at fault.
I am using the on-chip Intel HD4000 graphics and sound on an Intel i7 processor, installed on an Asus P8H77-M PRO motherboard, running Windows 8.1, connected by HDMI 1.4 through a Yamaha RX-V500D receiver to an LG PH670V television.
Has anyone any idea where I am going wrong?

This message was edited 3 times. Last update was at May 27. 2014 15:10

mike.T

Member Joined: May 17, 2012 05:05 Messages: 67 Offline

May 28, 2014 12:52

Hi,

As far as I know, if you connect the HDMI via Intel GPU, the audio output would be the same bits/sampling rate/channels only when compressed out (You select Dolby/DTS Bypass mode). If it's LPCM, then it would be down sampled because the chip does not support protected audio path for LPCM and by AACS Rule, PowerDVD had to down sample it.

There're some old document there explaining why:
http://www.bit-tech.net/news/hardware/2007/10/08/powerdvd_ultra_audio_downsampling_explained/1

Korrigan

Senior Member Joined: Oct 06, 2010 04:57 Messages: 221 Offline

May 29, 2014 09:25

Even if there was a HDCP problem, that would only affect bitrate and bitdepth, not the number of channels.

Is your PowerDVD set to bitstream high definition audio?

You may also try to enable "WASAPI Exclusive" in the Misc. tab of that setup dialog.

You can try running the Cyberlink BD Advisor: http://www.cyberlink.com/stat/bd-support/enu/index.jsp
and see what it says.

This message was edited 3 times. Last update was at May 29. 2014 09:33

My collection: http://www.blu-ray.com/community/collection.php?u=194008&action=showcategory&category=1&categoryid=7

werner

Newbie Joined: Jun 11, 2014 14:09 Messages: 4 Offline

Jun 11, 2014 14:37

i also have this problem.
dts is no problem and can be played

but when i play a movie http://download.dolby.com/Content_Download/ChannelCheck.m2ts
i get only audio if i set it to pcm decode and than all audio is played through 2.0 speaker

but i have set it up to 5.1 at the moment.

videocard is amd 7950 and audio is going through hdmi to my denon avr-x4000

why does the sample video not transmit audio to my orther speakers

Korrigan

Senior Member Joined: Oct 06, 2010 04:57 Messages: 221 Offline

Jun 11, 2014 15:21

That file outputs on all 5 channels here when I set it to LPCM decoded by PowerDVD, AMD R9 290x outputting to a Pioneer VSX-322 linked to a Toshiba TV.
But I get no sound at all when I set it to bitstreaming.

I just double checked, and the same file is bitstreaming just fine using MPC-HC (Media Player Classic - Home Cinema).

So yeah, there's a problem with PowerDVD indeed. My collection: http://www.blu-ray.com/community/collection.php?u=194008&action=showcategory&category=1&categoryid=7

werner

Newbie Joined: Jun 11, 2014 14:09 Messages: 4 Offline

Jun 11, 2014 16:10

i have no option like bitstream or lpcm decoded
only what i have is
pcm decode by powerdvd
non-decode dts
non decode
only the first works but that is only pcm2.0 de rest no sound

and when i play dts is does this directly play 5.1

Korrigan

Senior Member Joined: Oct 06, 2010 04:57 Messages: 221 Offline

Jun 11, 2014 16:13

Pretty much what I was saying.
First option is decoding by PDVD and then sending it to the receiver.
The two other options is what is called bitstreaming.

The first works in 5.1 for me though.

Check your windows sound configuration and make sure your HDMI output is set to 5.1 and not 2.0. My collection: http://www.blu-ray.com/community/collection.php?u=194008&action=showcategory&category=1&categoryid=7

werner

Newbie Joined: Jun 11, 2014 14:09 Messages: 4 Offline

Jun 11, 2014 17:58

i have already done that, and it is correctly set, soon need to change is to 7.1 because my old 5.1 sound system i wil hook up to my receiver to get the maximum of 9.2 sound

werner

Newbie Joined: Jun 11, 2014 14:09 Messages: 4 Offline

Jun 12, 2014 18:38

what i forgot to say,
whit powerdvd13 i had the same problem, so the problem acours also longer than powerdvd14

also when i select diffrent option in powerdvd i get audio, but when i play orther sounds on pc than the audio does not come to the speakers anymore, so powerdvd does some system changes and does not reset is after that

johnfv

Newbie Joined: Oct 08, 2009 10:03 Messages: 2 Offline

Feb 15, 2015 10:54

Reviving this old thread because I am seeing this same issue. I configure PDVD 14 for "non decoded hd audio" and WASAPI using HDMI but when I play 5.1 LPCM it still converts to 2 channel LPCM. DTS and Dolby play 5.1 fine. I have tried multiple computers/graphics cards with the same result. Has anyone found a solution?

anonim

Newbie Joined: Jun 06, 2014 17:50 Messages: 14 Offline

Feb 15, 2015 12:13

I have so herself instead of 5.1 or 7.1 gives 2.0 only when switched to decode LPCM then gud. And yes. He wrote long ago this sense 0.

Monstieur

Newbie Joined: Jan 07, 2016 02:46 Messages: 3 Offline

Aug 30, 2017 15:50

Reopening this thread because it looks like a bug. It happens even when playing standalone files, not just Blu-ray.

If the file has multiple audio tracks (5.1, 2.0, 4.0), it uses the the first track by default and 5.1-channel mode works. If I change the track to 2.0 then it permanently gets stuck in 2-channel mode even if I choose the 5.1 or 4.0 track. If I go directly from the 5.1 track to the 4.0 track then 4.0-channel mode works. It looks like going to a 2.0 track breaks it. If the first track is 2.0, then it will get stuck in 2.0-channel mode when opening the file.