I am currently using the following version of the Linn Klimax DSM software:
Software Version: 4.104.518
Software Variant: Fw961
Roon typically fails to detect the Linn Klimax DSM when I initially launch the Roon app. It’s only after I stop and restart the Roon server that the Roon app is able to recognize the Linn Klimax.
The problem has been going on for quite some time and I believe it started after the Roon ARC update, but it wasn’t always like this.
I own two Klimax DSM on different locations, I’ve not had connectivity issues in years. From experience with debugging Roon>Linn issues back in 2019, providing a detailed description of your setup (as @Carl explained) is really useful.
Have you changed anything in your local network (router, switches, firmware) around the time this started happening? Reason I ask is that there are a few network settings that can interfere with good Roon>Linn functioning. From experience: I disable jumbo frames and IGMP snooping, and I avoid fancy managed switches. Linn streamers are a bit particular with respect to those matters, as discussed in their documentation.