[Wanderlei]

Updated to OpenElec 6.0, when I start playing video files with DTS or Dolby audio I get very loud speaker cracking popping, sounds unhealthy for speakers. Only when starting playback, then it plays perfect and same thing happens when stopping but much less pounced crack/pop.

R-Pii 2 > HDMI > Receiver, with passthrough enable. If its pcm or passthrough off it doesn't happen.

I remember it use to happen on 5.0.8 too but was very slight, that you not notice unless you really try to listen for it.

I do reset on audio options. Is there any audio option/settings that may help me?

[popcornmix]

Does enabling/disabling omxplayer affect it?

[Wanderlei]

Does enabling/disabling omxplayer affect it?

Yep, it does.

MMAL acceleration, harsh sharp speaker crack.
Omxplayer acceleration, very subtle soft pop.

[popcornmix]

What is make and model of TV/receiver?
Does TV support AC3 passthough? If so, do you get cracking if you bypass receiver and connect direct to TV?

[Wanderlei]

The TV is LG 55LA8600, the receiver is Sherwood RD6506. It will passthrough dolby and dts.

I change the way it was plugged in to this;

R-Pii 2 to HDMI to TV to Optical Cable to Receiver

DTS
MMAL acceleration, harsh sharp speaker crack.
Omxplayer acceleration, very subtle soft pop.

Dolby
MMAL acceleration,harp speaker crack.
Omxplayer acceleration, very subtle soft pop.

(sorry I edit, dolby reply)

[popcornmix]

I was more interested in leaving out the receiver completely and using the TV speakers. Do you get the cracks then?

[Wanderlei]

Gotcha,

R-Pii 2 to HDMI to TV

MMAL acceleration, I get constant static on dts and dolby.
Omxplayer acceleration, no problems at all.

[popcornmix]

I don't expect this is a new issue, we've just changed the default player from dvdplayer to omxplayer in OE 6.
I'd be interested if OE 5 behaves the same way with omxplayer disabled and MMAL enabled (I suspect it will, but if it doesn't then there is something to investigate).

Also do you have any other kodi device? I'd be interested if that also has the problem (i.e. is it kodi/AudioEngine related, or something in the Pi firmware).

[Wanderlei]

I don't have any other Kodi devices unfortunately.

I loaded up my backup of OpenElec 5.0.8 and tested with MMAL acceleration and did not get the speaker crack. I doubled checked that passthrough was enabled, and could see the receiver display showing dts or dolby when playing each.

[popcornmix]

I loaded up my backup of OpenElec 5.0.8 and tested with MMAL acceleration and did not get the speaker crack. I doubled checked that passthrough was enabled, and could see the receiver display showing dts or dolby when playing each.

Interesting. Can you try copying the start.elf and fixup.dat files from OE6 to the OE5 sdcard (make a backup of original ones first).
Hopefully that will work, and will tell whether the cracking is a firmware or a kodi issue.

[huizingajm]

I have several files that are DTS and Dolby. I have yet to experience this issue. I am using Pi2 to Onkyo Receiver to TV. Passthrough enabled. On OE 6.0

[Wanderlei]

Interesting. Can you try copying the start.elf and fixup.dat files from OE6 to the OE5 sdcard (make a backup of original ones first).
Hopefully that will work, and will tell whether the cracking is a firmware or a kodi issue.

Ok, when I copied OpenElec 5.0 start.elf and fix.dat to OpenElec 6.0, it fails to completely bootup. It will show OpenElec splash screen, version number but then just goes black screen and Kodi never loads.

What I did do is a complete fresh image of OpenElec to eliminate any settings, config files, etc. Still the same, MMAL will have speaker crack at start of playback, Oxmplayer does not.

I tried again copying OpenElec 5.0 start.elf and fix.dat to fresh install, failed to fully boot just like before.

I have had similar issue, way way back in the past too. I look back through my post history it was around OpenElec 3.0 and I say it stopped happening OpenElec 3.2. The amp is quite temperamental, would not surprise me if its something oddly specific with it.

[popcornmix]

Interesting. Can you try copying the start.elf and fixup.dat files from OE6 to the OE5 sdcard (make a backup of original ones first).
Hopefully that will work, and will tell whether the cracking is a firmware or a kodi issue.

Ok, when I copied OpenElec 5.0 start.elf and fix.dat to OpenElec 6.0, it fails to completely bootup. It will show OpenElec splash screen, version number but then just goes black screen and Kodi never loads.

No, I suggested copying OE6's start.elf/fixup.dat to OE5. Generally you can replace an older firmware with a newer one, but not vice-versa.

[Wanderlei]

No, I suggested copying OE6's start.elf/fixup.dat to OE5. Generally you can replace an older firmware with a newer one, but not vice-versa.

Sorry about that.

I moved OE 6.0 start.elf and fixup.dat to OE 5.0.8 and works perfect, no problem.

[popcornmix]

I moved OE 6.0 start.elf and fixup.dat to OE 5.0.8 and works perfect, no problem.

Okay, that suggests it is not a problem with the firmware but a kodi problem.

I suspect it's an issue with how the audio engine handles not having passthrough data to send (mostly at start/end of track).
I believe it outputs zeros when "muting" when in reality it should output spdif encoded silence, or pause burst frames.

Any sensible receiver would say the zeros are not correctly spdif encoded and will not try to make a sound.
That's why 99% of users don't have an issue. But it seems your receiver does something bad in this case.

It might be worth testing a Milhouse nightly build, where the player/audioengine code has been refactored. Not sure if it will help, but it's worth a try.