Hello everyone!

I have been using vMix and Dinesat 12 Visual (radio/streaming software) for a couple of months now. I bought two nearly identical PCs (differing only in the motherboards) to run each software separately, as recommended by Hardata.

Up until a couple of weeks ago, everything was running smoothly. vMix was successfully receiving the video and audio sent via NDI from Dinesat. At first, I was running vMix on the trial version, but after deciding to purchase the 4K license, things started acting up. A few days ago, I noticed severe video and audio stuttering in vMix—almost as if it were trying to play heavy video files while heavily thrashing disks.

Behavior details:

The videos look completely fine in the Dinesat preview window.

Sending only audio via NDI works fine.

If I lower the video quality, the stuttering decreases.

Troubleshooting context: I am unsure if this was triggered by a recent Windows update or the latest vMix update 29.0.0.49.

System Specs:

OS: Windows 11 25H2

CPU: Intel Core Ultra 7 (on both PCs)

RAM: 32 GB (on both PCs)

Motherboards: ASUS and MSI (with 2.5 Gb and 5 Gb LAN ports)

Network: Connected via a 2.5G network switch between both PCs.

Any guidance on what settings to check or how to troubleshoot this to get back to normal would be greatly appreciated.

Thank you for your time and help, community!

Best regards,

"Thank you for the suggestion. I tested it with NDI Studio Monitor, and the video and audio stuttering happens there as well, exactly the same way as it does in vMix.

If this is indeed a network issue, where should I start troubleshooting?

Regards.