NDI Screen Capture goes blank on output display with no screen activity

[Waji]

Want to use NDI Screen Capture to send computers display to a projector for use during church services. Testing before implementing and finding that the projector screen keeps going blank if there is no activity on the screen after about 3 to 4 seconds. If the has any kind activity like playing a video it remains on. This happens with both Screen Capture and the older Scan Converter.
Using ASUS Zypherus Laptop, ethernet networking, a Magewell NDI to HDMI decoder and an Epson projector.
I've already checked with Magewell and they said the decoder never stops outputting.
I'm trying to get another laptop of computer to try this with also.
Has anyone seen this or have any suggestions.

 

[TheJims]

Waji;
I have seen occasions on projectors where even if there is an HDMI 'source' that is outputting a signal, unless there is actual video being processed, the projector will shut down.

There should be a setting on the projector where it will go into standby mode after a period of inactivity. Maybe set it for a longer delay time (5 minutes?) or do not allow it to turn off at all.

 

[Waji]

This Epson projector has Sleep mode timer with is set to 0 (feature disabled) and a A/V Auto Mute timer which is set to 30 minutes.
I also tried connecting the decoder to a flat panel display and it does the same thing.

 

[Waji]

I just tried sending OBS Main output as NDI. Used a scene with static image sources. The source was detected by the Magewell decoder. I selected it and my flat panel display is showing the NDI feed without going blank like it does for the Screen Capture feed. So there is something different about the Screen Capture NDI output that causes the display to go blank without activity.

 

[Waji]

Okay, I think I have this solved now.
I don't need audio for these projector feeds so I had it set to silent in Screen Capture. Turns out that if I enable audio the video feed now does not go blank.
You don't need any audio data to actually stream. As long as the Magewell decoder detects the audio it works fine. You can tell if audio feeds are detected by browsing to the Magewell decoder and viewing the Signal page. It shows you Video Status and Audio Status. The Audio status section will not show on this page if no audio feed is detected.

 

[TheJims]

Maji;
That seems a bit weird, but strange things happen all the time in AV. If nothing else you can keep the audio going full boat through the decoder/converter and just turn the audio off at the projectors.

I hate workarounds like this only because gremlins can creep in and rear their ugly heads several years down the road when you've forgotten the process.

Good luck with the project and hopefully it fixes it permanently for you.