[Bug]: Variable latency, changing verery 30-40 min (NDI HX3) WIN10

[Maeldu83]

Operating System Version

Win 10

CPU

i5 14500

GPU

RTX 4060

NDI Devices

PTZOptics MOVE 4K

OBS Version

30.1.2

OBS Installation Method

.Exe

OBS-NDI Version

4.13.0

OBS-NDI Installation Method

.exe

[Extra] Installation Steps

No response

OBS Log [URL]

No response

NDI Version

5.6.1.0

Describe the bug

When adding my NDI PTZ Cameras into OBS thanks to the plugin, when i choose latency "normal" or "reduced", this one is not consistent over time.
I have another camera captured via hdmi filming a video syncing tool (to have a point of comparison). On the NDI cam when I reset the latency on the ndi source (because changing the latency setting resets the problem cycle) and select "normal" latency, i got 150ms latency with my other camera BUT after 30-40min the latency changes to 330ms, then after another 30-40min latency goes back to 150ms and again go back to 330ms after 30-40min and over and over again. This behaviour is the same with the "reduced" latency.
Adding framsync doesn't change anything, hardware acceleration has no impact also. The only way of getting rid of this variable latency is to select the "lowest" latency but the image is not very smooth when doing pan/tilt moves so I'm not very satisfied by this option.

Thanks

Steps to reproduce the problem

No response

Expected behavior

No response

Screenshots

No response

Additional context

No response

[Trouffman]

Thanks for reporting this. It this also happenning when you get it from another source (like studio monitor).
Do you have "Green ethernet" disable on you Network interface ?

[Maeldu83]

Hello,
I still didn't tried to use studio monitor to see if the latency changes. I'll do it soon.
Yes my ethernet is green light 1000mbps if that's what your asking :)

Also, do you know if having a little frame loss in the lowest latency mode is showing a problem ? I just have some little drops, it could be almost usable.

[Trouffman]

Lowest latency might drop some frame in order to prioritize latency.

I was not referring to the green LED but to an advanced setting in the device manager of your NIC (network Interface) called "Green Ethernet".

This can cause lagging/stuttering like you describe when this feature is Enabled on your network device.

[Maeldu83]

Ok but if we consider we have a perfect network, should the low latency mode not drop any frame ?

I don't have any "Green Ethernet" setting inside my router parameters ...

[Trouffman]

The Green Ethernet option is NOT on your router but in your Windows device manager advanced options for your network interface.

Anyway.
Can you reproduce this issue on other system?
I could not reproduce this on my systems.

[Maeldu83]

Ok so i had the green ethernet on my ethernet device. I deactivated it but the issue is the same (and this time the latency was growing over and over again !). In lowest latency mode, I got a very good result this time, very little frame drops, almost 100% fluid. But I still would like to use the buffer mode to avoid bad surprises ...
I will try to test on another PC.

Also, I tried to monitor my camera thanks to NDI studio monitor and with this software, no latency changing. So I really think this issue is obs-ndi linked.

[Trouffman]

Thanks for checking.

We would need a sure way to reproduce that issue.

If you can describe step by step (bullet point) how to reproduce this issue that will be welcome.

Also detail what you compare with. (Like the studio monitor on same platform etc).

This is necessary so it can be tested/reproduced (if someone has the same hardware) or tested of reproducible with other configuration.

[Maeldu83]

Hello,

For information, I tested on another PC (i7, RTX2080 SUPER, WIN10, not a fresh install contrary to my production PC) and I got the exact same issue on the same version of OBS with the obs-ndi plugin. Latency is changing every 30-40min with the buffered latency setting.

I don't know what to describe, I do nothing special ... My network is composed of a router ZTE MC801A, NETGEAR PoE Switch. My PTZ camera (PTZOptics Move 4K) is linked to the PoE switch with Ethernet cat7 and same for my PC.
I launch obs, set the latency of my camera to "normal (buffered)", make a window capture of a video/audio syncing tool and film my screen with my camera. I make a scene with the 2 PoVs (window capture & my camera filming my screen) and I let it run without recording or streaming. After 30-40min the latency changes and it does it again 30-40min later. If the latency has changed and I go to NDI parameters of my capture to change latency to "minimum" and go back to "normal" it resets the latency and I got the same latency as when I started the test.

When I used studio monitor to compare, I only displayed my syncing tool video on my PC and monitor my camera filming my screen with NDI Studio monitor. There were no latency change in this case (no OBS used).

I really need to get this working ... I hope we'll find the issue.

Thanks a lot.

[Maeldu83]

Hi ! Any news about this issue ?

Thanks a lot

[RayneYoruka]

Hi my best advice is that you use NDI bridge to transcode the feed and avoid any changes in latency.. this is the general advice with HX since it doesn't play too well with obs-ndi.

https://docs.ndi.video/tools/ndi-tools-for-windows/bridge