Tvheadend

Ok here is my setup:

Server > Raspberry Pi 3 b+, Raspberry Pi OS + HTS Tvheadend 4.2.8-34

Client > CCwGTV + Kodi + Tvheadend HTSP Client + USB Hub with Ethernet

So this is the behaviour, power up the Chromecast with Google TV, open Kodi, start playing a TV channel. Within 30 minutes the stream will crash with a message popping up saying the server is unreachable, it will immediately reconnect and pull down the channel list but you have to manually restart the channel playing.

The really strange thing is it will fail every 30 minutes whether you are playing a channel or not, it's not like you are guaranteed to get 30 minutes of a stream. If you start playback 25 minutes later the stream will crash within 5 minutes. It feels like there's some background process that triggers every 30 minutes causing this disconnection.

Here is what HTS Tvheadend reports after every crash:

2020-12-21 15:04:10.904 htsp: 192.168.0.66 [  | Kodi Media Center ]: Disconnected
2020-12-21 15:04:10.904 subscription: 0209: "192.168.0.66 [  | Kodi Media Center ]" unsubscribing from "Blaze", hostname="192.168.0.66", username="192.168.0.66", client="Kodi Media Center" 
2020-12-21 15:04:10.906 htsp: 192.168.0.66 [  | Kodi Media Center ]: Write error -- Broken pipe
2020-12-21 15:04:11.028 htsp: Got connection from 192.168.0.66
2020-12-21 15:04:11.029 htsp: 192.168.0.66: Welcomed client software: Kodi Media Center (HTSPv34)
2020-12-21 15:04:11.034 htsp: 192.168.0.66 [ Kodi Media Center ]: Identified as user ''
2020-12-21 15:04:11.036 mpegts: 634.167MHz in DVB-T Network - tuning on Sony CXD2880 #0 : DVB-T #0
2020-12-21 15:04:11.036 subscription: 0224: "192.168.0.66 [  | Kodi Media Center ]" subscribing on channel "Blaze", weight: 150, adapter: "Sony CXD2880 #0 : DVB-T #0", network: "DVB-T Network", mux: "634.167MHz", service: "Blaze", profile="htsp", hostname="192.168.0.66", username="192.168.0.66", client="Kodi Media Center" 
2020-12-21 15:04:12.066 subscription: 0224: "192.168.0.66 [  | Kodi Media Center ]" unsubscribing from "Blaze", hostname="192.168.0.66", username="192.168.0.66", client="Kodi Media Center" 
2020-12-21 15:04:13.066 mpegts: 658MHz in DVB-T Network - tuning on Sony CXD2880 #0 : DVB-T #0
2020-12-21 15:04:13.066 subscription: 0225: "epggrab" subscribing to mux "658MHz", weight: 4, adapter: "Sony CXD2880 #0 : DVB-T #0", network: "DVB-T Network", service: "Raw PID Subscription" 

Things I've tried to resolve this:

Reinstalled Pi OS + HTS Tvheadend
Switched Raspberry Pi to LibreELEC + HTS Tvheadend
Removed authentication and allowed anon connections
Disabled all EPG Grabbers bar 'Over-the-air: UK Freeview'
Factory reset of the Chromecast with Google TV
Using a different PVR client on the CCwGTV - same behaviour
Using VLC on the CCwGTV connecting directly to the stream - same behaviour
With and without Ethernet
Changed Ethernet cables
Enabled 'Prevent updates during playback' option in PVR & Live TV settings
Enabled 'Don't cache in local database' option in PVR & Live TV settings
In CCwGTV disabled power optimization options for Kodi
Changed the energy saver mode in CCwGTV
...plus more that I can't remember.

Also, installed Kodi onto an Ubuntu VM and streamed TV fine for hours. Just imaged OpenELEC onto an old MXQ android box I had lying around and it's been playing happily away for the last hour with no disconnects.

I have a strong suspicion that it's either something Chromecast with Google TV is doing, or something TV Headend is doing that Kodi on CCwGTV just can't handle.

I'm open to any suggestions?