Question / Help NDI Stuttering

[nerdypastor]

We're a church and using an NDI signal from our presentation software to display song lyrics on the screen while we worship. Both OBS and the presentation software is running on the same computer. It worked well last Sunday. However today we experienced stuttering from the video. It was fine in OBS but the actual stream on Facebook was choppy while lyrics were displayed. Sound was fine. Video was stuttering. Everything was fine when the lyrics went away.

Any solutions? ideas? Here's the video of the livestream if you would like to check it out.

Week 5 of "Sync" - Online Service | We're excited to be LIVE again at 10am! Feel free to invite some friends to watch and share this morning's service! | By tfreechurch | Facebook

We're excited to be LIVE again at 10am! Feel free to invite some friends to watch and share this morning's service!

www.facebook.com

 

[Narcogen]

Please post a log with your issue! Here's how...

 

[nerdypastor]

I believe this will be the logfile.

 

[Narcogen]

Your NDI input is lagging, meaning that your computer is having difficulty keeping up with encoding/decoding it.

09:46:02.631: adding 23 milliseconds of audio buffering, total audio buffering is now 69 milliseconds (source: NDI™ Source)
10:20:24.485: adding 23 milliseconds of audio buffering, total audio buffering is now 92 milliseconds (source: NDI™ Source)
10:20:53.504: adding 23 milliseconds of audio buffering, total audio buffering is now 116 milliseconds (source: NDI™ Source)
10:40:53.917: adding 23 milliseconds of audio buffering, total audio buffering is now 162 milliseconds (source: NDI™ Source)

This isn't massive, but can be noticeable; audio and video should stay in sync, but the delay will become noticeable the higher this value gets.

11:12:25.327: Video stopped, number of skipped frames due to encoding lag: 34036/262271 (13.0%)

Your encoder is overloaded. The CPU cannot keep up with the load of running OBS, the NDI sources, and the presentation. This amount of encoding lag would be quite noticeable.

General Performance And Encoding Issues

OBS Studio - Free and open source software for live streaming and screen recording - obsproject/obs-studio

obsproject.com

You should also update as you have 25.0.0 and 25.0.1 was released on March 19.

 

[nerdypastor]

Your NDI input is lagging, meaning that your computer is having difficulty keeping up with encoding/decoding it.

09:46:02.631: adding 23 milliseconds of audio buffering, total audio buffering is now 69 milliseconds (source: NDI™ Source)
10:20:24.485: adding 23 milliseconds of audio buffering, total audio buffering is now 92 milliseconds (source: NDI™ Source)
10:20:53.504: adding 23 milliseconds of audio buffering, total audio buffering is now 116 milliseconds (source: NDI™ Source)
10:40:53.917: adding 23 milliseconds of audio buffering, total audio buffering is now 162 milliseconds (source: NDI™ Source)

This isn't massive, but can be noticeable; audio and video should stay in sync, but the delay will become noticeable the higher this value gets.

11:12:25.327: Video stopped, number of skipped frames due to encoding lag: 34036/262271 (13.0%)

Your encoder is overloaded. The CPU cannot keep up with the load of running OBS, the NDI sources, and the presentation. This amount of encoding lag would be quite noticeable.

General Performance And Encoding Issues

OBS Studio - Free and open source software for live streaming and screen recording - obsproject/obs-studio

obsproject.com

You should also update as you have 25.0.0 and 25.0.1 was released on March 19.

I figured this was going to be my issue. If I run the presentation software from a separate computer and then run the signal in to the computer that is streaming, that should be ok, yes?

Do you know... would I do this with USB? HDMI?

 

[Narcogen]

A video capture device, one that inputs HDMI and connects to your computer via USB3.

Compatible ones are made by Elgato, Magewell, BlackMagic, AJA and many others.

 

[Rossco]

We're a church and using an NDI signal from our presentation software to display song lyrics on the screen while we worship. Both OBS and the presentation software is running on the same computer. It worked well last Sunday. However today we experienced stuttering from the video. It was fine in OBS but the actual stream on Facebook was choppy while lyrics were displayed. Sound was fine. Video was stuttering. Everything was fine when the lyrics went away.

Any solutions? ideas? Here's the video of the livestream if you would like to check it out.

Week 5 of "Sync" - Online Service | We're excited to be LIVE again at 10am! Feel free to invite some friends to watch and share this morning's service! | By tfreechurch | Facebook

We're excited to be LIVE again at 10am! Feel free to invite some friends to watch and share this morning's service!

www.facebook.com

It sounds like there are two instances of audio present. As if the audio from the board is being mixed with live audio from an on board computer mic. Check your enabled audio sources. I did not see video stutter which is the problem we are facing. Songshow plus is choking for us. I just upgraded video card to GTX750i but it did not help. I noticed the NDI setting is set for 60fps and OBS is 30fps so I am going to see if matching those settings may be a solution.