Ive seen issues posted where people out of nowhere couldnt stream anymore without getting this error. I recently bought an unmanaged switch and magically my issue went away. I went back to the managed TP-Link Omada ER605 V2.6. Issue came back. I then tried my TP-Link ax3000 and again I got real-time buffer too full. I went back to my Trendnet TEG-S762 Unmanaged switch and the issue goes away. Also there is no issue plugged straight into the cable modem. I have opened task manager while I stream to see how much data Im uploading. The managed router and switch will not let me stream at 30mbps. The unmanaged switch will. The "real-time buffer too full" error has a direct correlation to managed switches and routers not letting me get to 30mbps. I bounce everywhere between 2 and 15mbps on the managed devices while streaming however my speed test gives me a full 40mbps upload EVERYTIME. There is no speed limit set in the devices. They have stock settings. I am hard wired to each device when tested. What setting in these managed devices could be stopping me from being able to stream? When I turn the stream quality down to 15mps or even 10...still wont send it with the managed devices. Im streaming to youtube if that matters.

If you have an Omada managed switch, you need to check the port configuration to make sure you have the right port speed, etc. Sounds like vmix is being throttled.

Of course you shouldn't have to do it.

A managed router ought to be able to note the flags in the vMIX IP data stream noting time sensitive content and properly prioritize it. But obviously some do not or they may have default limits set for new equipment added to their network so you need to make sure your equipment is given a higher default by communicating with the network people for the site you are at so they'll be able to make the changes required to let your stream work and even ask them what they have that is limiting it and what they have to change. And that is something you actually should be doing.

You could even be so kind as to post back here with what you learned so the next poor soul trying to figure out the same problem stands a greater chance of finding the answer instead of having to play hunt the Wumpus like you've been forced to do.

Anyhow, best of luck getting this figured out, it can be so frustrating to have stuff like this happening.

I just noticed something strange about the OP's post.

Both of the devices he was having problems with, aren't switches, but are routers (that also have a built-in switch). When he replaced that with a standalone switch the problem went away. I would suspect the problem was not with managed vs. unmanaged, but rather using a router vs. a standalone switch.

Now we all go through multiple routers to reach the destination, so I'm not saying that the simple act of using a router is the culprit. But there does seem to be something going on with the OP's network.

DeanJohnsonProductions, do you also have issues when streaming OBS with similar settings as vMix, when using the routers?

Welcome to the wonderful world of networking. Lots to learn, even more things to go wrong. When talking to the on site IT people, ask them friendly to:

1. Provide enough bandwidth for your upstream stream but also downstream traffic.
2. Deactive all IDS systems, content filters etc.
3. Deactive all SSL breakup units in the network path.
4. Avoid any bandwith throttling in sitwches and routers.
4. Basically give you a direct internet access with nothing in between.

Things for you to check:

1. Is there enuogh bandwidth on site? Check this before setting up there.
2. Are you going over business fiber, copper DSL or even mobile networks?
3. If you are on mobile, try to avoid RTMP and go with SRT.
4. By all means make sure you are streaming with constant bitrate (CBR). Be sure to check this, I think it is not activated by default.
6. Set your bitrate to 60-80% of the available link bandwidth. (Check this with a Speed Test

Make sure you gain some network knowledge or have somebody to help you. Things are getting more and more complex.

Good luck,

Christian