Buffering on Android TV (logs attached)

Plex Media Server NAS & Devices
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Server Version#: 1.22.3.4523 on WD NAS PR4100
Player Version#: Android TV 8.18.2.25850 (0905fbb3)

I am having lots of trouble streaming some 4K movies to my Android TV from my NAS server. I get very bad buffering, and I don’t know why.

My NAS is wired via ethernet to my router. My Android TV is on 5Ghz WiFi to my Android TV (and not too far apart).

The Android TV is connected to my Denon AV via HDMI.

I don’t think the issue is video, though I could be wrong. Reason I say this is the only common denominator is the fact that the buffering is always when I’m streaming videos with TrueHD audio. On Kodi, it doesn’t buffer but I don’t get the TrueHD audio - but this could be a red herring.

I have uploaded some logs, can anyone help? It is driving me nuts.

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No log files attached to your post.

FYI, make sure your server is set for debug, not verbose, logs (debug is the default level). Verbose logs too much information and the log files quickly wrap. It makes it difficult to find necessary information. See Reporting Issues with Plex Media Server for information on setting the log level.

Android TV make/model?

Denon model?

Is the video or audio transcoding?

Play a video with TrueHD audio selected and subtitles turned off.

Monitor playback in Plex Dashboard → Now Playing. Expand the view to show details. Attach a screenshot if possible.

Let the video play for ~30 seconds. Stop playback. Wait ~1 minute. Pull the log files and attach to the thread. Drag the ZIP file into the message window. It will attach at the cursor location.

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Sorry, not sure why logs didn’t attach. Regardless, I scrapped them and redid them as per your instructions.

Denon AVRX4500H
Sony Bravia KD85XF8596BU

Not sure what you mean about audio and video transcoding. Hopefully you will see on the logs, it is pushing Dolby Digital to my AVR, if that’s what you mean.
Plex Media Server Logs_2021-06-13_20-43-05.zip (3.3 MB)

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Settings: In the Plex app on the Sony, make sure passthrough = HDMI. It will not help in this specific instance, but will help with other audio formats.

Thanks for the log files.

To make sure I understand things:

  1. If you play a movie/show with TrueHD audio, playback repeatedly buffers.
  2. If you play the same movie/show with Dolby Digital (AC3) audio, it plays fine.
  3. This happens for all, or most, movies/shows with TrueHD audio, not just one or two.

Correct?

I believe you are running into the limitations of using the Plex TV apps and running Plex on a low power NAS.

As mentioned earlier, the Plex TV app cannot pass TrueHD audio to the Denon. Therefore, the Plex Media Server transcodes (translates) the audio to Dolby Digital Plus. This is what happened when you played Back to the Future III. You can see this visually (instead of digging through log files), using the previously mentioned Plex Dashboard.

Your NAS has a low-power Pentium N3710 CPU, which has a Passmark score of 1353.

It may simply be struggling to transcode the TrueHD audio, especially if this happens with most or all movies with TrueHD audio. The NAS will struggle more with the higher bit-rate movies, such as 4K or high-bit rate 1080p movies. You can sort the libraries by bit rate to test.

The easiest workaround is to choose an alternate audio track, such as Dolby Digital, if available. Dolby Digital, Dolby Digital Plus, and dts should direct play (i.e. not transcode), reducing the load on the NAS’ CPU.

All Blu-ray movies that have TrueHD audio also include a Dolby Digital version of the soundtrack. You may need to re-rip the disc or re-acquire the movie if the Dolby Digital track is no longer available.

If you want to have TrueHD audio, including TrueHD + Atmos, you will need to acquire a Nvidia Shield Pro and connect it to a HDMI input on the Denon. The Shield will passthrough TrueHD audio to the Denon without any transcoding.

1 Like
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Thanks for these replies, it is really helpful and appreciated. You are correct in your 3 questions.

So, am I to assume a pass mark of 1353 isn’t great?

Thanks for the suggestion about the Nvidia Shield. That looks to be a separate device, and with the way my AV is stored away, it would be a tight squeeze. Could something smaller suffice? I looked at this, for example: Amazon Basics HDMI To HDMI + Audio (SPDIF + RCA Stereo) Audio Extractor Converter https://www.amazon.co.uk/dp/B07KRWYN4R/ref=cm_sw_r_cp_api_glt_fabc_JC5MVTX1J5CNWRT3CC3X

Or is that wishful thinking?

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An external adapter won’t help.

The problem is the limitations of using TV based Plex clients. It cannot send TrueHD audio out the HDMI port to any attached device, whether a receiver, soundbar, audio adapter, etc.

You have options:

  1. Do not play TrueHD audio
  2. Use a Plex client that does not transcode TrueHD audio
  3. Use a Plex server that can transcode TrueHD audio.

The first option is the easiest - choose the Dolby Digital audio track instead of the TrueHD audio track. The Dolby Digital track is (should be) available, as it is included on Blu-ray discs that have TrueHD audio. You will most likely hear no audio difference, as you are not currently hearing TrueHD audio (Plex is transcoding it to another format).

The second option is where the Shield Pro comes into play. The Shield Pro will passthrough TrueHD audio, unaltered, to your Denon receiver. It will not be transcoded (converted) by the Plex Media Server. This has two advantages: First, you will hear unaltered TrueHD audio, including TrueHD + Atmos; Second, the load on the server is less as it does not have to convert the audio.

The Shield Pro is the only off the shelf Plex client that reliably passes TrueHD + Atmos audio. The non-Pro Shield (“tube” model) is not recommended. It has trouble with with audio drop-outs when playing some 4K HDR movies with TrueHD audio.

The third option is to run Plex Media Server (PMS) on a more capable system. This does not mean replacing the WD NAS. For example, you could run PMS on a PC, leaving the media on the NAS. You could test this by installing PMS on an available desktop or laptop (Plex does not limit the number of servers for single account).

You do not necessarily need a powerful PC to convert audio. I run Plex on a Synology DS918+, which has a Celeron CPU. It is not without its own limitations, but it can convert TrueHD audio without buffering. The Celeron is a low power CPU, but is more capable than the Pentium in your WD (Intel “pecking order” is generally Pentium → Celeron → i3 → i5 → i7 → i9).

1 Like
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Thanks for all your detailed explanations. I realise I could switch tracks, but I got an Atmos surround sound system integrated into my ceilings and walls, so I wanna put it to good use.

To that end, the Shield Pro is going to look like it is my best bet! The only drawback I see is space and the fact I kind of like just running stuff off my TV, rather than a separate HDMI source. Still, in the grand scheme of things; this is minor.

Thank you again for breaking all this down and helping me out.

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