You may need to get to that outlet.
There is a loose wire somewhere. Check the other outlets in the room as well because the problem can be in the next outlet. Go to Lowes and purchase a plug in outlet tester, item number 292767. It is only $3.98. This will tell if you have power and if the outlet is wired correctly. Most electrical home builders wire outlets and switches by poking the wires in the back of the devices. To me, this is unsafe. An outlet is not a wire nut, it is a device. Many times I have serviced houses where the wires have backed out or burned up due to constant heat or continuous plugging in and unplugging.
You may want to do this to your entire house.
My method is to rewire all the outlets by first counting you outlets. Buy six inches of 14-2 or 12-2 romex, I usually use 14-2, and two red wire nuts for every outlet. Turn off the power, cut off the outer jacket from the romex, toss the ground wire, cut the wires 6", strip all the wires about one inch on both ends of the black and white, curl one end of each wire making a hook, and pre wire or re-wire all the devices to one screw and one screw only on each side of the outlet. Black wire goes on the brass screw and white wire on the chrome screw. The bare conductor stays put on he green screw. This is the PIGTAIL method. Google it to see how it is done. Do not use the poke thru method. Wire nut the wires accordingly color to color and reinstall in the boxes. If you take the time to take out all outlets by pulling the straight out, you will probably find a wire has come loose. By doing this, this will save you a lot of headaches down the road. As far as your switches, just cut the wires from the back as short as you can and strip and hook them back on the screws.
If the next outlet is the problem it would not work, right? They all work except for behind the tv entertainment center. Somehow we will check that outlet. Not sure how we will do it because of the weight but that must be where the problem is. thank you
You will nee to pull out the next outlet, nearest the panel that feeds the house. If all wires are in good contact then you have some heavy moving to do. Keep me informed. I am waiting.
If you pull out the outlet(s), the the wires on one or more should just kinda fall out. Hopefully the outlet is not burned. To avoid this problem again, go back to the part that starts with "My method is to rewire all the outlets." Just make sure you turn off the power first.
We'll have to wait until tomorrow for some help and will get back to you.
Please follow up with me regarding this. My personal advice is to rewire everything. Not all tomorrow but at least fix the problem not. The poke though method on the outlets is a fire hazard. Good luck and God Bless. You will get a follow up message after this.