My guess is it's a setting on your TV. I suggest you consult your TV's manual.
If that doesn't help, post back with your TV model number and a detailed description of how your TV is connected to your FiOS set-top-box.
Enjoy.
Press the pip button on the bottom of the remote 👍
As this thread is now over two years old, it will be locked in order to keep discussions current. If you have the same or a similar question/issue we invite you to start a new thread on the topic.