[CarstenS]

Not sure if that is caused by Kodi or by my HTPC setup in general, but:

When using Kodi as an input source, my TV (LG OLED65C8LLA) goes off exactly every 15 minutes. No interaction with any of the remotes (TV, AVR) or mouse (Kodi/HTPC) can prevent this from happening. There is no "no input" or something - the TV goes off straight away. Power saving on all devices is turned off. I do not experience this issue with any other input source though.

The only actual change in my setup that might correlate with this was an upgrade from Skylake to Kabylake on the CPU of my HTPC (running Kodi on OpenSuse linux on an 
Asus ROG Strix B250G board).

Has anyone seen a similar issue or could point me to any other setting that is worth investigating?

[Klojum]

Never heard/seen this problem before, perhaps OpenSuse itself is having a power/suspend/screensaver action active after 15 minutes?
Did you also update the BIOS of the motherboard for the Kabylake upgrade?

I'd try a different OS with Kodi, e.g. running LibreELEC from a USB stick, and see what happens.

[CarstenS]

Never heard/seen this problem before, perhaps OpenSuse itself is having a power/suspend/screensaver action active after 15 minutes?
Did you also update the BIOS of the motherboard for the Kabylake upgrade?

I'd try a different OS with Kodi, e.g. running LibreELEC from a USB stick, and see what happens.

I double-check the BIOS, but it is up to date. I also switched off 'fast boot' (saw this as a recommendation somewhere else) so far without success. There is no power saving elsewhere configured. 

Will try LibreELEC over the next couple of days.

[CarstenS]

It seems I got rid of this problem. I added the following lines into my /etc/X11/xinit/xinitrc:

xml:
xset s off

xset -dpms

xset s noblank

So it was definitely caused by the power management - although it should have recognized that Kodi is playing and should not switch the TV off.