My vmix 4K production PC is: i7-9700K, 16Gb, RTX2060S with Blackmagic Decklink Duo 2 AND Decklink Duo. (==2 PCMCIA capture cards). PC is clean and only used for vMix and has been running vmix error-free for tenths of long broadcasts (vmix is great!) I run vmix 4K 23.0.0.67, but I also run SRT tests using the latest 24.0.0.5x

I'm using Larix broadcaster in local Lan via Wifi and sending SRT. I typically send 1280x720p50 with 4Mbps H.264, my vmix works as SRTListener with set 500ms delay. Project master framerate is usually 1080p50.

Network works flawless without packetloss.

What happens is that after some time (about 15mins) the SRT connection starts to loose frames (source dropped & resync) and the image starts jumping and becomes really choppy, totally useless. Closing & recreating input doesn't help, start & stop stream in Larix doesn't help. Only thing that helps is a restart of vmix and then it works again OK for about 15mins. vmix SRT stats looks clean: no packet loss, RTT 2ms. Overview stats start to show big share of source dropped & resync.

The more inputs I have in the preset, the more quickly this starts, but I have been able to reproduce the issue with only a small preset with 1 camera input (decklink duo 2) & STR Listener and no streaming & fullscreen & external output.

I have a secondary streaming laptop (asus rog strix i7, gtx1660, vmix HD) with same preset, connected to same network and I can send the same SRT stream from LArix to 2 listeners simultaneosly and the laptop receives the SRT flawless for infinity while the production PC starts loosing frames.

So something in the vmix / vmix config causes this.

Any suggestions to try next?

Thanks,
-severi