They would say that wouldn't they. When I had my issues with a brand new KDL I too was apparently the only one experiencing the TV rebooting itself every couple of days while watching a program, lip sync issues and lost signal on certain channels that were miraculously found after a TV reboot . They blamed everything from my PVR, the HDMI cables, power supply and eventually even arranged for a local serviceman to come over twice and take a look but couldn't find anything wrong and insisted that it could be my HDMI connections or PVRs. When TV continued to have these issues with nothing else plugged in he blamed spikes in power supply. Since there was no errors in the service menu and TV didn't reboot itself while the serviceman was looking at it I could not prove that is faulty to return it to shop. I put up with the crappy TV for nearly 6 months with Sony telling me I was the only customer experiencing these issues before the first firmware update came out and fixed the lip sync and lost signal issues. The second firmware update a month or so later fixed the self rebooting issue as well later. So keep nagging them and shame them on Facebook until they fix the issue because you are NOT the only one with this issue. Google is your friend and for every one who complains or looks for a solution online there are probably hundreds of others who simply accept whatever Sony tells them.
On my TV after the last update the self rebooting restarted again and after the factory reset with latest firmware now instead of TV rebooting every couple of days it stops working with 6 red light flashes and logs the backlight issue logged in the service menu. There is nothing wrong with the TV that a couple of minutes with power removed won't fix so my guess is that all along the issue with self rebooting was the LED voltage going outside the tolerance set in the firmware.
With Lollipop once the LED voltage went above or below the limit it would trigger an error code and force the TV to reboot. I'm guessing that in Marshmallow Sony "fixed" the issue Sony by either increased the voltage limits or removing backlight LED voltage checks from its firmware until they got rid of TVs and boards already in stock.
With Nougat firmware I'm guessing they returned voltage checking to firmware and this will trigger the error on the older TV boards with some rebooting the TV while others turn it off with 6 flashes of red light . With my TV out of warranty and Sony likely to charge more then a new TV to fix the problem its a lost cause unless they allow us to downgrade the firmware. While I'm trying to find a way to downgrade the firmware on the Sony I went and bought a cheap Bauhm from Aldi , doesn't have the brightness of the Sony but won't be going off half way through a program either .
I'd check the service menu for errors if you haven't done so yet and if you have backlight LED errors in the log try reducing the brightness to lowest setting that is still watchable.
Good luck.
