[ChrisKlondike]

A Pi is absolutely fine as a standalone single and dual tuner TV Headend server if correctly set-up.  If you also want to run Kodi on it - then a Pi 4B+ properly set-up should also be fine if you aren't hammering it, recording everything to the internal SD card etc.  

Personally I'd be fine with my Pi 4B as a combined TV Headend+Kodi solution for non-intensive use cases (travel etc.) but I'd alway recommend separating the TV Headend backend from the front-end. (Even 2 Raspberry Pis for instance)

The Pi 4B with a Pi Foundation TV Hat is a really neat solution as a single tuner TV Headend back-end server for instance.

My guess is that your TV is coming on because for some reason your Kodi PVR client is losing connection with your TV Headend server (running on the same board at local host 127.0.0.1) and that's triggering a 'Connection Lost' warning (these can be turned off). That connection lost warning is causing your Kodi to come out of screen standby and trigger the TV to come on via CEC.  Disabling Connection Lost warnings - which is Settings option for TV / Live TV - will stop that - though I don't know why it would lose connection.

I take it you're running LibreElec with the TV Headend Service Add-on and the TV Headend PVR Client ?

Thanks again. Yes, I'm running those things. I disabled the "Switch to Kodi when it wakes up" entry in the UI already but this happens anyway when it reboots.
Anyway, I'm not upgrading hardware. Next time it sh*ts on me, I'll install something other than TVH.

So you have disabled the CEC entry to switch back to the Pi when the Pi comes out of screen saver mode - but your Pi is rebooting (which it shouldn't).  The reboot will assert a CEC switch-over as standard I think - so that UI entry can't change that behaviour.

The question is why your Pi is rebooting - that's not normal.  Most spontaneous reboots are usually caused by power issues. 

1. Are you using an official Raspberry Pi foundation PSU - most of the recent Pi models need more current than most basic third part USB PSUs will supply (particularly phone chargers)
2. Are you using an external hard drive for storage - and is that powered separately (either as a mains powered solution or via a powered USB hub if the drive is bus-powered)

Thanks Noggin, I left this thread for a while of relatively good behaviour from Kodi, but it's "worn out" again and so I had to rebuild it.
I am using a 2amp power supply though it is not the Raspberry Pi model, and a beefy cable to the Pi.
I am using a powered USB hub, which powers the tuner dongle and the HDD.
Logs never show anything about why any reboot happened.

[ChrisKlondike]

I was thinking about the DVB tuner device possibly being bus powered.  Most will probably draw more power than a PI can ideally provide and make the system unstable.  A bus powered HD would likely be the same issue.   Using a powered USB hub for anything like this is I believe recommended  and probably even required for things to work well.

Thanks Bluzee, I am using a powered hub.

[mcelliott]

The official Raspberry Pi 3 power supply is 2.5A, which would suggest that your 2A power supply might be on the limit.

You have your hard drive and TV tuner connected to the same USB 2 port on the Pi, so that any recording data has to come in to the Pi and back out on the same port.

Personally I use a 128GB microSD card in my Pi4 and I've recorded loads of stuff over Christmas. If I need a little longer to watch stuff, I can move files to my NAS. How much storage do you need for recordings? Do you really need the 1TB drive?

All I'm thinking is that perhaps you are seeing a perfect storm of issues. Maybe (as someone else has suggested) the hard disk is going into a low power mode and needs time to come back up. Maybe your power supply is on the limit. Maybe you are placing too much demand on one USB port. A lot of what you are describing seems to be Kodi crashing, or Kodi losing the connection to TVHeadEnd. It doesn't look like an issue with TVHeadEnd itself.

You've suggested that maybe the Pi3 is marginal hardware. I don't know. I've not tried to use TVH on a Pi3. However, over Christmas I had 5 programs simultaneously recording using the three USB tuners directly attached to my Pi4 TVH server. They were recording to the MicroSD card, and Kodi was playing one of the recordings at the same time. I don't know how close to the limit this was, but it all worked fine. With a fair wind, Kodi and TVH on a Raspberry Pi can be rock stable.

Maybe I'm a bit risk-averse, but the first thing I would do is configure my network to assign a static IP address to the Pi. Then you can get rid of 127.0.0.1, and replace it with a 'proper' IP address. Not sure if it will help, but it's hard to see how it will hurt. Unless you also switch your modem/router off overnight, of course.

[ChrisKlondike]

The official Raspberry Pi 3 power supply is 2.5A, which would suggest that your 2A power supply might be on the limit.

You have your hard drive and TV tuner connected to the same USB 2 port on the Pi, so that any recording data has to come in to the Pi and back out on the same port.

Personally I use a 128GB microSD card in my Pi4 and I've recorded loads of stuff over Christmas. If I need a little longer to watch stuff, I can move files to my NAS. How much storage do you need for recordings? Do you really need the 1TB drive?

All I'm thinking is that perhaps you are seeing a perfect storm of issues. Maybe (as someone else has suggested) the hard disk is going into a low power mode and needs time to come back up. Maybe your power supply is on the limit. Maybe you are placing too much demand on one USB port. A lot of what you are describing seems to be Kodi crashing, or Kodi losing the connection to TVHeadEnd. It doesn't look like an issue with TVHeadEnd itself.

You've suggested that maybe the Pi3 is marginal hardware. I don't know. I've not tried to use TVH on a Pi3. However, over Christmas I had 5 programs simultaneously recording using the three USB tuners directly attached to my Pi4 TVH server. They were recording to the MicroSD card, and Kodi was playing one of the recordings at the same time. I don't know how close to the limit this was, but it all worked fine. With a fair wind, Kodi and TVH on a Raspberry Pi can be rock stable.

Maybe I'm a bit risk-averse, but the first thing I would do is configure my network to assign a static IP address to the Pi. Then you can get rid of 127.0.0.1, and replace it with a 'proper' IP address. Not sure if it will help, but it's hard to see how it will hurt. Unless you also switch your modem/router off overnight, of course.

Thanks for these suggestions. I've run Kodi on this Pi and others and they all suffered similarly. The only common thbing is the tuner dongle, so I'm thinking I'll get another one and see if that fixes it.

[mcelliott]

so I'm thinking I'll get another one and see if that fixes it.

Try an x-box tv tuner (if you need DVB-T). Cheap on eBay, and pretty good in my experience. I'm not sure where in the world you are and what TV standard you are using.

[noggin]

so I'm thinking I'll get another one and see if that fixes it.

Try an x-box tv tuner (if you need DVB-T). Cheap on eBay, and pretty good in my experience. I'm not sure where in the world you are and what TV standard you are using.

I cannot recommend the Xbox One DVB-T/T2 tuner for UK use.  It has some major issues (low sensitivity and refusing to properly tune and demodulate some muxes at all in my experience). In London it was terrible on an aerial/antenna feed which was 100% error free with other USB DVB-T/T2 tuners (PCTV 290e, Win TV Dual HD, August T230 Mk1, HD HomeRun Dual and HD HomeRun Quad).