A bit of update on my case.
After one week of not having TV the repair guys called me to say that SAMSUNG is OUT of stock of the spare parts and they don’t know what to do?????????????????????
SAMSUNG ???? REALLY???
What is going on here had the television less than a week (Samsung Q9FN 55) and all I get is off, on, off on I tried everything. I feel like I have flushed money down the toilet buying this tv now.
I’m about to try my 3rd Q875 in 82 days. Both lasted exactly 40 days and became useless power cyclers. Fortunately Best Buy has a 45 day return, so the 3rd is coming Tuesday. Seems all the lower level support people are very familiar with the problem. One told me my model number of the last one was from a “bad batch”. Of course the supervisions do not acknowledge any issue. I just got off the phone with a supervisor an I will know tomorrow if they will do what she suggested. If they do I will pride them all over the internet , we will see.
Sadly I too have come across this problem on my 65" Q7FNAFXZA. Brand new and hasn't been in use for more than 10 days, and now is basically a giant paperweight in my living room. I contacted support and they sent out a tech 4 days later, and replaced the OCB, the OCB cable, and the main board, and you guessed it, still constant power cycling. After five phone calls to support, and three to the 3rd party tech company to update the ticket, I've finally been "escalated" to Case Management, but after two separate occasions of being on hold for 40 and 65 minutes, I gave up. The tech diagnosed that the actual panel needs replacing, but at this point it would be a completely refurbished TV!!! Hoping a moderator sees this and can assist with either a refund or exchange ASAP. BEYOND FRUSTRATED!
Same problem all around the world with Samsung tv's and they put tag "solved" on that issue.....amazing! Now they have us as walking adverts of Samsung tv's around the globe.
I had this exact same problem but found out in my case I needed to replace ALL my HDMI cables.
samsung sent me a new one connect cable, same issue, John Lewis completely replaced the whole tv, same issue, but this time reboots occurred 10-20 times a minute.
That’s when I decided to start different cable setups. Not sure why as my hdmi cables are not that old but replacing them with 2.0b cables fixed the whole issue. Not a single reboot now.
Hopefully someone will find this info useful