Good to hear, @sa2000. The cpp-netlib project released version 0.13.0 (stable) in January 2019. Looking at PMS on my Mac it appears to have the libcppnetlib-uri.dylib library included (as opposed to the full-blown cpp-netlib library) in its Frameworks folder.
Reading the docs for the URI library, it appears to be what is responsible for parsing URIs (duh 
) and is likely what is being used to process the SSDP responses from devices on the network. Unfortunately, for some reason, the library included in the MacOS PMS distribution doesn’t have a valid version number set for it (at least that I can see by querying it with otool; it returns a “current version” of 0.0.0, as do many of the libraries bundled with the PMS app).
However, I note that PMS 1.14.1.5488 (the first version we observed this behaviour in) was released to beta on December the 17th 2018 and the latest version of the URI library (1.1.0) was on November 24th, 2018. Could it be the new version of this library that caused the issue (assuming Plex is keeping up to date with the releases of the open source code it relies on)? Nope, don’t think so…read on…
/me Googles for a while…
Ah, found another thread where someone else came to a similar conclusion: Plex consuming a full core at idle, libcppnetlib-uri.so (boost) implicated
So, tinkering with my Synology box, I thought I’d drop the libcppnetlib-uri.so file from the 5470 build into my current production system (1.15.4.993) and see if it resolved the problem. Strangely, I can’t find the libcppnetlib-uri.so file in the installation package for earlier versions.
edit I just rolled back to 5470 on my Synology and it doesn’t have libcppnetlib-uri.so installed at all, so I’m guessing the use of that library was new (or changed) as of 5488. I checked older versions of the macOS distribution and these, also, do not include libcppnetlib-uri.dylib in versions prior to 1.14.1.5488
