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duncanthrax
Linux receiver loses audio after ~4.5 minutes in multicast mode
So about 4 minutes and 30 seconds into running the Unix receiver on my Linux box, sound cuts out. Restarting makes it work … for the next 4½ minutes.
tcpdump says I’m not receiving packets anymore. And then I am again after restarting the client. I have opened 4010/udp in the firewall (duh).
It works if I put the server in Unicast mode. Same firewall settings. Is that a known Linux issue? Running Fedora 32.
What network equipment to you have in your LAN? This sounds like a multicast switching problem. Any "smart" switches that use IGMP snooping?
Any "smart" switches that use IGMP snooping?
Nope, just a “dumb” Gigabit switch.
Honestly if this isn’t a common issue and/or you don’t know what’s going wrong immediately I don’t need you to spend your time on it. Unicast is working fine for me, I was just wondering what’s going wrong with multicast.
There are occasional problems around multicast, but not very common.
The symptoms "first works, then after some time cuts out and works again when restarting receiver" is typical for problems around IGMP snooping (when you restart the receiver, your kernel will send a fresh IGMP group join message, which will "repair" the group->port association in the switch, until it times out again).
If your switch has a web interface, log on there, search for options like "IGMP snooping" or "multicast helper" and turn all of that off.
It’s an unmanaged switch, no interface of any kind.
Edit: should be able to try running the client on a laptop later and see if it’s a specific issue with that one PC.
Make sure that IGMP is allowed through your firewall. If you're using firewalld, add the protocol to the zone that your host is in. In my case I'm running a Win10 vm on a linux host, so I have to enable the IGMP protocol for the zone applied to the internal bridge interface br0.
I'm having a pretty similar issue, between my Linux pc and Win11 pc, but the qemu vm connection works without issue on the Linux PC, but when ever the Win11 PC is transmitting audio it just stops after a short time, and I need to stop and start the scream client on Linux too much for it to be reliable.. I don't know which mode the Win11 scream is in, I just use default as that has worked pretty well in the past.. I'm using the latest scream, as I update it mostly when I have issues with it..
I have a similar problem but unicast works well. Host: Ubuntu20.04 Guest: Win11
