I had the same problem, too, turning on and off, I thought it was the tv but, fortunately, I had and have a piece of equipment by the name of the 'Monster Power' (MP) which indicated 134 watts was being fed into the house. When I googled what MP's said about that number, their website claimed that I should not see more than 125 watts being fed in from my electric company.
Then I called the electrical company and told them my problem, they told me that they would send a tech out to check the issue within 48 hours. However, that was before I told them that my MP was showing 134 watts. So, before we hung up, I then told her the MP was showing 134 watts was being fed into the house, then she sounded concerned and, immediately, said she would get them out there within the hour. And, they were here within a few minutes and the equipment worker, immediately, turned off the power for the whole block and did some major work here which took several hours. When electric came back on my MP began showing the range was then within 121-124 watts, and has remained consistent for the last 2 years, thanks to my MP.
Now, this makes me wonder if this is the reason that too much electricity being powered into our homes and, ultimately, into the household equipment may be the reason our electrical equipment seems to go out, one right after the other. I used to say back in the day, that when my electrical equipment would go out pretty much, either simultaneously or one right after the other, that it was just the luck of the draw. I also put surge protectors into my outlets, too because I know that power surges can blow out or wear on our expensive equipment. However, not when the tv goes on and off, like mine did, as you described, and I found the culprit which may have saved mine and possibly save my neighbor's equipment thanks to my MP. Hope my experience helps anyone who may be reading this message.
