I just want to chime in that I don’t mind testing with PCM but I had enabled passthrough specifically for Dolby Atmos. I’m not glad that anyone else is experiencing this, but am glad that I’m not the only one.
is it true that passthrough and having Plex convert to PCM are bit for bit the same ? in other words no loss of quality ? i prefer passthrough for the Atmos bits however.
I have the same problem, intermittent times throughout the movie I get a millisecond drop of audio. The video continues without issue, the audio stays totally in sync and it may happen 2-3 times per movie at seemingly random intervals. Impossible to reproduce with consistency. If I go back and replay the part where the audio dropped, it plays fine all subsequent times.
I think it’s happening on all my DTS Master audio and TrueHD movies, not just True HD / Atmos like the thread title, but I haven’t paid that much attention. I just figured it was every blu-ray movie in my collection. It never happened in PHT which I used for at least 1 year before switching to PMP.
I’m on the latest versions of PMP and PMS. I have an Onkyo TX-NR636 receiver using HDMI only from an nVidia GeForce GTX 970. I have 7.2 speaker setup and a Benq Projector using all redmere active HDMI cables. Following the Plex Audio Configuration guide, it tells me I should not enable pass through, but if I don’t hit that checkbox for Advanced Settings, and subsequently place a check mark near every codec type, I don’t get 7 channel audio. When I disable passthrough, and try to let PMP handle the audio, my receiver reports it’s getting 2.0 channel stereo and it outputs “All Channel Stereo”. I have definitely set my channels to 7.1 in PMP, so why does PMP only output 2 channels. Why do they recommend so heavily to let Plex handle the decoding or better yet, how do you get that to even work? As soon as I check the box for pass through on the various codecs, my receiver reports the input to be 7.1 DTS+MA and output is the same and it sounds fantastic (other than the random drops).
@drshaw said:
I have the same problem, intermittent times throughout the movie I get a millisecond drop of audio. The video continues without issue, the audio stays totally in sync and it may happen 2-3 times per movie at seemingly random intervals. Impossible to reproduce with consistency. If I go back and replay the part where the audio dropped, it plays fine all subsequent times.I think it’s happening on all my DTS Master audio and TrueHD movies, not just True HD / Atmos like the thread title, but I haven’t paid that much attention. I just figured it was every blu-ray movie in my collection. It never happened in PHT which I used for at least 1 year before switching to PMP.
I’m on the latest versions of PMP and PMS. I have an Onkyo TX-NR636 receiver using HDMI only from an nVidia GeForce GTX 970. I have 7.2 speaker setup and a Benq Projector using all redmere active HDMI cables. Following the Plex Audio Configuration guide, it tells me I should not enable pass through, but if I don’t hit that checkbox for Advanced Settings, and subsequently place a check mark near every codec type, I don’t get 7 channel audio. When I disable passthrough, and try to let PMP handle the audio, my receiver reports it’s getting 2.0 channel stereo and it outputs “All Channel Stereo”. I have definitely set my channels to 7.1 in PMP, so why does PMP only output 2 channels. Why do they recommend so heavily to let Plex handle the decoding or better yet, how do you get that to even work? As soon as I check the box for pass through on the various codecs, my receiver reports the input to be 7.1 DTS+MA and output is the same and it sounds fantastic (other than the random drops).
I’ll answer my own question-- even though I thought I previously had configured this, I just needed to configure my “Playback Device” inside the operating system to be a 7.1 system. The OS that my HDMI output was 2 channel stereo. So even if you set your channels in PMP, you need to make sure the OS also has the correct channel outputs for Plex to handle the audio streams and send the individual channels in PCM. In the next day or two, I should watch a movie and see if the drops have been eliminated. I do like that the audio starts right as the video starts this way. When passthrough is enabled, there is 1-2 seconds of silence while the video plays before the audio joins in.
Although, I did just notice this in the 1.1.6 release notes:
PMP now selects multi-channel audio over stereo if your system is configured for more channels than 2 in settings.
Wonder if my problem was solved by coincidence with the new version that I applied last night and not necessarily setting the channels at the OS level. Oh well, it works. ¯_(ツ)_/¯
interesting, I have not updated yet but did test a dolby True HD movie with 5 brief drop outs , will refresh and test again
Would it help to include PMS logs during the same time frame?
No, PMS is likely not involved in this.
I just needed to configure my “Playback Device” inside the operating system to be a 7.1 system. The OS that my HDMI output was 2 channel stereo. So even if you set your channels in PMP, you need to make sure the OS also has the correct channel outputs for Plex to handle the audio streams and send the individual channels in PCM.
In theory, “Exclusive Mode” (which is enabled by default) should avoid the need for changing OS settings.
@vlang said:
Would it help to include PMS logs during the same time frame?
No, PMS is likely not involved in this.
I just needed to configure my “Playback Device” inside the operating system to be a 7.1 system. The OS that my HDMI output was 2 channel stereo. So even if you set your channels in PMP, you need to make sure the OS also has the correct channel outputs for Plex to handle the audio streams and send the individual channels in PCM.
In theory, “Exclusive Mode” (which is enabled by default) should avoid the need for changing OS settings.
i can tell you I have exclusive mode set and OS to 7.1 but still get drop outs with True HD , though i still have to update to the latest media player version. will double check settings and try again
thanks for all your help !
@Playdance: we were talking about something else… it’s not directly related to the dropouts. We still don’t know what causes the dropouts or how to fix it.
On this topic can anyone else confirm if you bitstream a truehd or atmos track and skip forward or back a few times (press up or down) you will lose audio completely and have to restart the movie? Dont know if this is related, if anyone else can confirm this issue as well. I opened another thread on the topic.
@Ghostm said:
On this topic can anyone else confirm if you bitstream a truehd or atmos track and skip forward or back a few times (press up or down) you will lose audio completely and have to restart the movie? Dont know if this is related, if anyone else can confirm this issue as well. I opened another thread on the topic.
I have not noticed such an issue and I’m experiencing the audio drops intermittently on TRUEHD tracks. It might take a second to sync but it always does.
@prange said:
@Ghostm said:
On this topic can anyone else confirm if you bitstream a truehd or atmos track and skip forward or back a few times (press up or down) you will lose audio completely and have to restart the movie? Dont know if this is related, if anyone else can confirm this issue as well. I opened another thread on the topic.I have not noticed such an issue and I’m experiencing the audio drops intermittently on TRUEHD tracks. It might take a second to sync but it always does.
Hmm interesting and you tried the scenario of selecting a truehd track (I mainly reproduce this on atmos tracks however) and hitting up and down a number of times?I didnt notice it either until i specifically tried it. I tried on my rx 460 graphics card and my integrated apu and every time i press up or down a a number of times on a truehd or atmos track (skipping forward or back) i lose audio until i restart the movie.
It does not happen to me in plex home theater so i have to assume this is a plex media player issue…
I see this is still an issue…used PMP tonight, latest version, and had this TrueHD drop out 3x during a 2h15m movie.
Windows and the overly complicated WASAPI Protected Audio Path rearing its ugly head again. Check your HDMI Audio drivers and make sure they are the latest ones from NVIDIA. If they are you may want to roll back to a previous version that was a known working set.
I’m not sure I concur that it’s a driver issue as OpenPHT has no issues playing the same TrueHD audio. I honestly have no idea what version may have worked previously since I don’t use PMP full time. I only install and test new versions occasionally as I still don’t like the layout of it compared to PHT/OpenPHT, but I know it’s the future direction of the Plex team none the less, so I give it a try once every 4-6 months.
I submitted logs earlier in this thread and there was nothing to be found as did others.
I’ll look at the Nvidia drivers as I’m not sure how old they are. They are certainly not the most current as there was never a need to update them.
Moved to a new 4K TV to which OpenPHT seems to have problems exiting the app with, so I’m tentatively using PMP full time now…ugh
Updated drivers a week ago. Played a TrueHD movie tonight (13 Hours: The Secret Soldiers of Benghazi) and in true form, dropped audio 3 times during the movie for a split second. Since there has been no movement on this thread, I’m assuming there has been no resolves found for this?
I was experiencing this as well with TrueHD but not DTS MA. The way I solved this was to uncheck all formats, disabling passthrough. I haven’t had any problems since. Apparently PMP can’t bitstream TrueHD properly.
You shouldn’t have to disable all formats, just the TrueHD one. That being said, I haven’t tried it myself because I’m stubborn and was hoping that was a quicker turn around on a resolve by the dev team, but this seems to be a stubborn one that they have said they haven’t been able to figure out.
I did a quick search on the bug/issues reporting site noted as a sticky at the top of this forum and didn’t find it there.
Has this been listed as an official bug? Or am I just not finding it?
I recently got an Atmos setup and haven’t had any issues with dropouts. My system is configured as can be seen in the screenshots and I haven’t paid attention to the Windows settings before and while it says 2-channels the Atmos demo videos sound amazing and I definitely have surround sound. The receiver also show Atmos/DTS-X correctly based on the audio format in the different files I have. Am I missing out on something or am I just lucky it works without issues?
Yeah I’m not sure if the Windows settings have any bearing anymore. My Windows Settings are configured to 7.1
The only difference in my PMP settings is that in Device, mine says ‘AutoSelect’ where yours is blank.
In my PMP Video settings, the Sync mode is set to Audio, what is yours set to?
It could also be that it’s highly subjective to the files being played. I play original movie files done by MakeMKV.
Or you could just be lucky 
Either way this is still an issue that isn’t exhibited in other players. Vlang have you had any luck in tracing down what is going on here? Is there anything we can provide or test?
I was going to upload another log, but again, just like my first one, it showed everything being fine, yet 3 times during the movie, the audio would drop for a fraction of a second.
