Said in advance: I don't need help. I'm describing my adventerous experience only, but would be happy to get some opinions.
I have 6 identical small HTPCs since years at home, each with it's own TV or TV+5.1 setup and all of them are running LE (OE in the past). All HTPCs are booting/running LE from network and are having a more or less identical setup.
Yesterday I switched from Leia to Matrix with a reserve HTPC (same hardware as the other 6) and a completely new setup/config. All was working fine for hours, so I deployed the working setup to the server.
In the evening I turned on th HTPC in the living room, which is connected to a HDMI-Receiver/home theater, which in turn is connected to a 55" LG TV (55LA7408). The experience was a completely disaster: The HTPC slowed down after relatively exact 5 minutes, eating up it's remaining RAM in further ~30 seconds, throwed an OOM and restarted LE. This then repeated constantly.
Today I was busy with debugging and after hours I've found that the LG TV was still connected to the LAN, but "unaddressed" by DHCP and firewall 'cause of privacy converns (I left the TV connected in the past for further experiments in the future). After disconnecting the LAN cable from the TV this spooky adventure has ended. And this is the interesting thing; When leaving the LG TV switched on and connected to the LAN, all HTPCs in the LAN are having the issue decribed above.
Which now leaves me puzzling is, what has changed in LE/Kodi? Some automagic detection of "Smart Dirt" (can't write the correct word here because of f*ckin' censorship) ? What was the LG doing in the LAN...broadcating to hell?
At the end my realization and advice is: disconnect all these shitty smart things from your network or replace it's software with open source, where applicable.