Does the TV electrical plug into a wall outlet or into the back of the FIOS box?
If you are plugging it into the back of the FIOS box I suggest you move it to a standard wall outlet (if possible).
The box should not matter but what model STB do you have from Verizon.
You indicate you manually turn the STB on and off so I assume you mean you press the button on the front of the STB to turn it on and manually turn the TV on. Is that true?
I have a samsung LED TV and previosuly had a 6416 and now a 7232 and haven't experienced the problem you describe.
You say it is not a remote issue. But if it is, this information may be helpfull to you or other users. Also the 58" TV being plugged into the STB may not be a good idea. Not sure what power switching capacity the STB has, and would need to look it up. To protect your TV investment, I would say get a seperate good quality surge protector and give it a dedicated power source.
The first, or older remotes have a power button that turn on and off both TV and STB with the same button. They can get out of sync. If you plug the TV into the STB, this can make matters worse, or more confusing. Make sure the STB is on and press just the power button on your TV to get things back in sync. Or aim the remote at the TV so only the TV can see the remote signal once the STB is on. Even though the newer remotes only control two devices, I like them because or the seperate STB and TV power buttons that do not send out both the TV and STB on/off signal at the same time.
If you want the Power Key to control only one device at a time…
To power any device, you will need to press the appropriate Device Key, then the Power Key.
1. Press and hold the STB key.
2. While holding down the STB key, press OK.
3. Release both keys. The Device Keys will blink twice.
4. Press 9 - 7 - 7. The STB key will blink twice.
5. Press OK. The STB key will blink 3 times to indicate success in programming.
The original setting for the Power key depends on which remote you have. (Please check the Play / Pause key on your remote to see which remote you have.)
Now this is odd. Sure your just not trying to get the 7232 DVR without the upgrade fee. Just kidding, and don't mean to insult you. I supplied any information I could come up with, and it looks as if everyone else covered things very well. Let us know what happens today.