Pausing Live TV creates an Error

[bcm00re 18]

So I tuned to my local CBS channel (and wait 15-20 seconds for the picture to come up) then I pressed pause.  After a 30 seconds or so the program un-paused and started playing despite no one even touching the remote.  So when that happened I paused it again, but this time about about 30 seconds I got an error and I was no longer tuned to the channel.  I was able to reproduced the problem when I tried it a second time -- see the two attached transcode logs as well as the server log that covers both.

 

I am using a Roku Premiere and the Emby app Version 3.0, Build 52.

transcode_pause1.txt

transcode_pause2.txt

server_pause.txt

[Luke 37053]

What times did each of these events occur? thanks !

[bcm00re 18]

Shortly after 10:18pm and shortly after 10:30pm is when I first attempted to pause each.  On both, I paused almost right after I finally got a picture -- so it should be early in the transcode log (because the log didn't start until I attempted to tune into the channel).  I think I saw errors for both in the server log.

[Luke 37053]

Hi, can you try again and see if this was an anomaly? We are unable to reproduce. Thanks !

[bcm00re 18]

I was able to duplicate it again, but this time it acted a bit different.  Like last time, I paused it shortly after the picture came up, and after pausing for a bit it started playing again on its own.  I then paused it again, and after a short time paused it started playing again on it's own.  I did this one or two more times, then finally when I tried to pause the program the error occurred.  This time I noticed that when trying to pause all but the first time, I had to hit the pause button twice.  It's like when it started playing on its own it still thought it was paused -- so the first time I hit pause the symbol changed from the pause symbol to the play symbol then on the second one it changed back to a pause symbol and the program actually paused (but only momentarily).

 

See attached.  My transcode log starts at 11:24 so the error occurred a short time after that.

transcode_pause3.txt

server_pause3.txt

Edited November 6, 2017 by bcm00re

[Luke 37053]

Can you reproduce this with the web app?

[bcm00re 18]

That's a negative.  Using the web app, the first time I hit pause it does it and seems to remain paused indefinitely.  I should point out that when I duped it earlier tonight I was using an Roku Express -- not the Premiere I used last night.

[bcm00re 18]

Any ideas on a possible workaround for this (based of what you are seeing in the logs)?

[ebr 14910]

Can you please try with the beta version of the app?

 

Thanks.

[bcm00re 18]

I was actually using the Beta version of the app. As stated above I was using Emby app Version 3.0, Build 52 (the non-Beta is Build 50). Or is there a new Beta now for me to test?

[ebr 14910]

There is a new version for you to test.

 

Thanks.

[bcm00re 18]

Awesome! I will try to take a look this evening and report back.

[bcm00re 18]

I gave Build 53 a try -- and the results were a bit different.  First of all, I never got the crash/error BUT I still was never able to successfully pause Live TV.  I tried to pause at least 10 times, but every time the program was start playing again on it's own a few seconds after I had paused it.  And like last time, when I tried to pause it again I had to hit the pause button twice before it paused (with the first one changing the pause symbol to the play symbol and the second one changing it back to the pause symbol).  After 10 or so attempts, when it started playing again on its own I did a rewind back to the start of the program and watched a couple seconds of it then hit pause -- again it only stayed paused for a short time then started playing on its own.  At that point I exited back to the Emby guide.  See attached logs...

transcode_pause4.txt

server_pause4.txt

Edited November 7, 2017 by bcm00re

[ebr 14910]

I cannot make that happen.  I have tested pausing for up to 5 minutes without issue.

 

Can you please reproduce the problem and follow the instructions for sending an in app log?

 

Thanks.

[bcm00re 18]

App log was just sent.

 

I attached a video too -- it is really a MP4 file that I renamed to TXT so I would be allowed to upload it.  You can see I pause the video shortly after it starts playing, then around the 2 minute mark it starts playing on it own.  You then see me hitting the pause button twice to get it to pause again.  Then after a much shorter time it starts playing again autonomously; once again you'll see me have to hit pause twice to get it to pause.  I was going to wait for the video to restart on its own a third time, but decided to stop my phone's recording before it got too big.

pause.txt

Edited November 7, 2017 by bcm00re

[ebr 14910]

Everything looks fine on the app side.  For some reason, the player simply refuses to remain paused.

 

I was able to reproduce but it took 30 minutes for the player to start back again on its own for me.  I was able to re-pause, back up, go forward etc. just fine though.

 

I'm stumped...

[bcm00re 18]

Okay, thanks for looking into it. Let me know if you want me to try anything else. FYI, I have duped this on three different Roku models: a Primeire, an Express, and a Roku 3 (that latter of which has a wired ethernet connection). So I might try some other channels and/or turning off the HDHR Extend's hardware transcoding and see if the behavior changes for me.

[speechles 1917]

When you pause, the roku itself becomes the buffer. Depending on the model of said roku device, this buffer may be smaller or larger due to different memory sizes. The roku requires at least 25MB or so of free ram to keep the video player in a usable state. When it falls below this, the roku usually spontaneously reboots. This happens more frequently as apps update and add new things. The apps become larger in size, and these memory limits affect directly how long things can be buffered and remain in a playable state. It looks like the roku now chooses to unpause itself rather than crash into a reboot of the device.

 

https://en.wikipedia.org/wiki/Roku#Feature_comparison

 

Use that chart above to see how much memory comes which each device. The devices with 256MB are definitely having issues. The ones with 512MB should only experience it after long durations of pause. The 1GB models should see this too, but only after extremely long durations of pause. The roku4 with its 1.5GB of ram should last the longest of all.

 

Keep in mind, the firmware itself occupies a certain percentage of RAM at all times. Much like windows 10 requires 1.5GB just to run itself, before you ever add in applications. You have to learn to live within this limitation with roku as you can't just add more RAM.

[ebr 14910]

When you pause, the roku itself becomes the buffer. Depending on the model of said roku device, this buffer may be smaller or larger due to different memory sizes. The roku requires at least 25MB or so of free ram to keep the video player in a usable state. When it falls below this, the roku usually spontaneously reboots. This happens more frequently as apps update and add new things. The apps become larger in size, and these memory limits affect directly how long things can be buffered and remain in a playable state. It looks like the roku now chooses to unpause itself rather than crash into a reboot of the device.

 

https://en.wikipedia.org/wiki/Roku#Feature_comparison

 

Use that chart above to see how much memory comes which each device. The devices with 256MB are definitely having issues. The ones with 512MB should only experience it after long durations of pause. The 1GB models should see this too, but only after extremely long durations of pause. The roku4 with its 1.5GB of ram should last the longest of all.

 

Keep in mind, the firmware itself occupies a certain percentage of RAM at all times. Much like windows 10 requires 1.5GB just to run itself, before you ever add in applications. You have to learn to live within this limitation with roku as you can't just add more RAM.

 

Ah, I didn't think about the fact that maybe the Roku was still actually requesting the stream instead of stopping.

 

That makes sense then and, instead of crashing, it is just continuing playback so you don't lose any content at the end.

[Luke 37053]

When you pause, the roku itself becomes the buffer.

 

This isn't true with segmented formats like HLS and mpeg dash. They offer just in time delivery. The Roku is not obligated to continue downloading segments while paused, although it's possible that their implementation is doing that.

[speechles 1917]

This isn't true with segmented formats like HLS and mpeg dash. They offer just in time delivery. The Roku is not obligated to continue downloading segments while paused, although it's possible that their implementation is doing that.

 

According to tablo:

Roku devices don't have an infinite buffer for LIVE streams. What this means is that while you're watching live tv the Roku will keep requesting segments of the playlist until its pause buffer is full, then it will automatically resume while it dumps the old segments from the buffer to make room for the new ones. Those streaming at higher resolutions (like 10 Mbps) will see a shorter time window between the pause and the buffer overflowing (2-3 minutes) vs. a lower stream (3 Mbps) where it will be between 20-30 minutes.

[Luke 37053]

Right - tablo might not be segmenting and could instead be sending the entire raw stream. In that situation, when you pause there's no other place to put the data except for the roku buffer which will quickly fill up.

[ebr 14910]

Based on what I (and the OP) have observed, it sure looks like the Roku is behaving the same way with hls.

[bcm00re 18]

@@ebr

What Roku model have you tested with?  You mentioned it took 30 minutes before yours un-paused.  Was the channel you were tuned to in HD or SD?

 

I have done most my testing with my newest Roku the Primiere model which has 1GB of memory so not sure why mine only stay paused for like a minute.  Both my Roku 3 and Express model have 512MB of memory -- so it's not like I using any with just 256MB.  I was tuning to a 1080i CBS feed that Emby Server was transcoding using QuickSync (but I wish it was using my Extend's hardware transcoded stream instead).

[ebr 14910]

I tested with a Premiere and, I believe, was tuned to a 720p channel.  The specific bitrate of the stream coming in would be a huge factor in this as well as any other apps on the device I imagine.