Linux Audio Phase issue.
#1
I am running a Onkyo receiver TX-SR606 along with my HTPC. The Onkyo is well known for the capacitors in the HDMI board to go bad.
I ran my HTPC (Ubuntu 14.x KODI with nightly updates) HDMI directly to my Vizio TV bypassing the Onkyo until I get around to operating on it.

Up until the release of Kodi 14.x the audio from the TV was fine when watching standard 2 channel stereo programming. After a few nightly updates later, I noticed what sounds like a Phase shift in the audio along with some Compression issues now with the audio over HDMI to the TV. The audio seems to clip the voice when there are any other loud sounds in the programming content such as incidental music in a specific scene, gun fire, explosions etc. It almost sounds like the voice is being sucked out. Something like the old trick of tying your speakers out of phase to suck out the vocals. I find that I have to turn up the sound quite a bit now to hear the voices. As soon as there is only dialog the voices are fine. Yep, I'm getting old, but my hearing is not that bad yet.
I tried everything I could think of via KODI audio settings and I even have tried some PulseAudio and Alsa settings with no change with the issue.
I is a Broadcast Engineer and usually can fix any hardware with a good hammer, screwdriver and the occasional propane torch. Puns and grammar intended Wink I can get lost pretty easy with most software issues.

Any help in this situation would be greatly appreciated.


Thanks
G
Processor: AMD Athlon™ 64 X2 Dual Core Processor 4000+ × 2
Memory: 2GiB
Graphics: GeForce 7050 PV / nForce 630a/integrated/SSE2
HardDrive: 320 GB
DVB: AVerTVHD MCE A180
Keyboard/Mouse: Wireless
OS Type: 14.04 64-bit Trusty
Kodi: 14.x
Receiver: Onkyo TX-SR606
TV: Vizio 42" LCD
Computer was formerly a Captiveworks 3000 HTPC
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#2
Hi GEEMac,

my Denon X2000 has a audio restorer function. Has your Onkyo a similiar function?
When the restorer is enabled and I watch movies with good audio Quality (Bluray), then the dynamic from the signal is limited which results in the same behavour which you described.
Try to disable all audio signal processing functions from your Onkyo and hear if it is better.
I hope this helps.
Latest news about AudioDSP and my libraries is available on Twitter.

Developers can follow me on Github.
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#3
Hi Wisler

The issue is with the HDMI to the Vizio TV. I had to bypass the Onkyo due to a few bad capacitors on the HDMI switching board. This is a known problem for this model Onkyo. I hope to get to that soon with some higher temp capacitors. And while I'm in there a couple of low noise fans on the heat-sinks.

I am running HDMI from my HTPC directly to the TV for now, so it is audio via HDMI. It worked fine until a few nightly updates after the release of Helix, then the TV audio started to sound as stated above. As for 5.1 surround, I have a TosLink Optical connection also coming from the HTPC to the Onkyo if I want 5.1 for now since the HDMI board is not switching.

So it all boils down to something that may have changed in Kodi that has the audio out of phase via HDMI. I haven't seen any ALSA or Pulse Audio updates for a long time now, so I can't say it is either. If I run anything else with audio over HDMI into the Vizio TV it's fine, the voice is OK and no phase issues with SMPlayer or VLC just Kodi. I have been in the audio settings of Kodi a few times in case I missed something and I don't see anything there to correct the issue. I also have been in ALSA and PulseAudio and did not see anything there.
The only problem is if I start tweaking the settings in ALSA or Pulse it will probably mess things up when I get back to HDMI to the Onkyo.

This is why I asked in the other thread about the possibility of a setting for phase in the DSP to correct the issue within Kodi.

I'll keep picking at it until I find what I may be missing or maybe one of the Devs will possibly find and and correct anything if needed.
Processor: AMD Athlon™ 64 X2 Dual Core Processor 4000+ × 2
Memory: 2GiB
Graphics: GeForce 7050 PV / nForce 630a/integrated/SSE2
HardDrive: 320 GB
DVB: AVerTVHD MCE A180
Keyboard/Mouse: Wireless
OS Type: 14.04 64-bit Trusty
Kodi: 14.x
Receiver: Onkyo TX-SR606
TV: Vizio 42" LCD
Computer was formerly a Captiveworks 3000 HTPC
Reply

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Audio Phase issue.0