Audio dropping out when playing videos

I’ve experienced something I haven’t with Caspar before and am looking for some clues. I’m introducing Caspar at a newish job to play commercials and other video elements during live sports. After random amounts of time, anywhere from a few minutes to an hour, the server stops playing audio. The video continues to play fine, but silently. If I restart the server things return to normal for a while. I’ve experienced this using the LTS 2.3 version and also one of the newer 2.4 versions.

The computer is about ten years old, with Windows 10, an i7 processor, 16 GB of RAM. It has a 1050 Ti GPU. All drivers are up to date. The system is set to 1080i5994, and all video elements are encoded to that standard. I’ve also experienced problems playing WAV files, for whatever that’s worth.

Any ideas are appreciated!

What output does Caspar use? Decklink or NDI or sctreen?

Decklink. I should have included that, thanks.

Is it a HP Z4?

No, it’s a computer I put together a long time ago. I donated it to the work since I didn’t need it easier and it makes my work life easier. It’s an MSI motherboard.

This is only a vague possibility - are you sure the Decklink has PCI Express 4 lane generation 2 (or better) with no other card sharing those lanes? There is a posting from 2021 (see Post 4295) that reported audio issues with Duo 2 which proved a lanes issue.

I have the same problem on a Dell 7960 with an RTX A4000 and 2x Decklink 4K Extreme 12G cards running on Windows 11. CasparCG 2.4. I use the AES output for sound. Video was 1080i5000 and a mov file. After running for about 20 hours, the sound was missing, including the embedded audio in the SDI. I was not present when it happened, so I couldn’t run any tests at that moment. However, the next day the server worked as expected when I started it.

From the CasparCG log, the only thing I noticed was that the reference signal had been missing and then returned just before the sound issue occurred. I tried removing the reference signal to replicate the issue, but the sound did not go away.

One last note: the Decklink Desktop Video software was not the latest version. Does anyone have any ideas whether this is a CasparCG issue or a Decklink problem?

This may not be the cause of the issues you experienced on the Dell, but server version 2.4 requires Decklink drivers version 11 or later.

See changelog.md for server 2.4.0 stable, Producer Improvements segment.

The current is 12.something, but I will update…

I have the same issue but I notice that the reference is lost and locked again then the audio is jittered or dropped, But it should not happen. While using any other software like vmix, OBS using the same decklink card and the same driver there was no problem only this issue happens with caspar cg

Thanks everyone for chiming in. I followed the advice on the linked post above, swapping the PCiE slots for my Decklink card and GPU, and that seems to have solved the problem.