What is causing plex to use CPU when idle?

[oubliette]

You might try this:

Plex consuming a full core at idle, libcppnetlib-uri.so (boost) implicated

I found the other thread (implicating UPnP) by looking at your recent activity - since I have manual remote access configured, and plex is the only thing running on this host, the workaround for me was: iptables -A INPUT -p udp --source-port 1900 -j DROP and restarting plex cpu is hovering at 1% (vs >=100%)

Though it’s possible that bug has been fixed and you’re experiencing something else.