Slow DVR Performance on 4th Gen Apple TV (Windows)

@Marino13 Can you run a speedtest as outlined above and post the results?

It's possible that a DVR server update is affecting disk read performance on Windows. What version of windows are you running?

Download
100.21
Latency
5.21
Jitter
0.29

WHS 2011

I have also verified that other media player apps play the files fine and skip instantly on the same exact files. All of the recordings in the DVR folder skip fine with MrMc, Emby and Plex with no transcoding.

Can you try measuring speed test downloading a recording. You will need a file ID from the Log, then download http://x:8089/dvr/files/ID/stream.mpg on the same computer and from another device and measure the download speed. If you download curl.exe you could run a command like this which would show speeds as it downloads:

curl.exe -o nul http://127.0.0.1:8089/dvr/files/123/stream.mpg

Alternatively you can feed that same url into MrMC and see if seeks also get slow there when reading the media from Channels DVR.

13 37

These are from two LAN connected PC's running Windows 10. 42 is the Ubuntu DVR and 77 is the Windows DVR. As you can see the Windows DVR is half the speed as the Ubuntu. For some reason when I run it locally on the server I get a curl: (23) Failed writing body (0=!27) error. My server doesn't have curl installed so I just downloaded the Windows version and threw it in a folder on the C drive. It may not actually be installed correctly. I can't seem to figure out how to input the url into MrMC. If you can guide me on where to go with that it would be appreciated.

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Same issue over here, I was running Channels DVR on a old MacBook (connected with Ethernet) and it worked flawlessly with ATV 4th Gen with Ethernet. I have since switched over to a windows server and it takes it a few seconds to seek on Ethernet while on WiFi it seeks quickly. How would the data rate change from Mac to Windows?

@Marino13 Do you mind running the curl tests again with the latest DVR pre-release? I'm testing here and it seems fixed now.

I can try this weekend. Out of town right now.

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The fix for this is available here: Channels DVR Windows recordings lags when skipping

I've noticed this problem too. AppleTV 4K since the latest update to tvOS. I don't particularly want to go messing with the windows settings since this PC has a lot of duties besides PVR. But it looks like you have a release imminent that can fix this?

We were unable to fix this on our end. The same code in our app seems to work fine against Mac and Linux servers, but not Windows. So it looks like this is a bug in Windows and the only workaround is to disable autotuning on the OS network stack.

This was not an issue early on in the Windows Channels DVR days. I used it from day one of release for several months (maybe even over a year) before I started having this problem. What changed in the code that it worked fine in the beginning and doesn't work now? Seems to me that if it was this autotune issue it should have acted this way in earlier releases.

I'm still not exactly sure, but I think there was a Windows update along the way that broke something. The TransmitFile function used to send files efficiently started behaving differently since Windows 10 build 1803

Others started noticing issues last summer as well: https://stackoverflow.com/questions/50706315/transmitfile-sending-the-same-bytes-again-and-again

The server I used for this (WHS 2011) has not had an update installed on it since prior to using it for Channels.

Good to know. My hunch is that the workarounds added to fix the broken behavior on newer Windows builds is causing performance degradation on both old and new builds.

I've only been using AppleTV/ChannelsDVR(windows) since late 2018 and experienced no lag, it's only in the past 2-3 weeks that it's been an issue. Everything otherwise up to date.

I've been having issues on my Apple TV 4K lately with doing the same thing. The DVR is running on my MacBook Pro. I ran the speed test and got this: Speedtest

Download
 25.81 
Mbit/s
Latency
 154.38 
ms
Jitter
 115.20 
ms

It is also freezing up every few seconds during playback. Nothing else being used to stream at this time.

25MBit/s speedtest points to a network problem. Maybe your Wi-Fi is overloaded or a neighbors router is interfering.

We strongly recommend wired Ethernet for the dvr and TVs if possible.

This only is ever an issue with DVR playback locally. I run so many streaming apps that do 4K video with no problem. I run the speediest app on the Apple TV itself and it always shows 50. It never stutters at all except for playing back a recorded show from the computer.