Don't worry. It's apparently a windows file transfer, since it randomly increases and decreases. This house isn't too hard to defend. Just get your bearings first. West is the little armory room next to the kitchen. You should go there first and grab a 240. This machine gun will make the defense a lot easier. The east is the front. The little side office tends to cover it pretty well. The north is that large circular area that Ozone should be covering.

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There are 3 entrances. They can come in the open gate in the basement and up the stairs. That's the one where we shot the 3 guys in the back. They can come through the door next to those stairs via the balcony. They can also come right in the front door.
The first wave is coming from the west. If you have them, lay down a few claymores on the steps. Then run into the outlook with all the machine guns. Use your heavy machine gun to fire on them as they come out of the woods. This gunfire and the claymores should take out most of them. When the wave runs out, turn and fire on the survivors as they come up the steps.
Things get a little hectic from here. The waves are a little irregular. Just move around and keep an eye out for the enemy. The stragglers should come in through the front door and balcony access. There should also be a half-hearted one wave through the front door. There are a few good places to camp out for the rest of the level. The top of the stairs is an excellent position. You can fall back to the bathroom if you're hurt, and you have a line of sight on the front door and a side door they'll use if they come up the stairs or the balcony. The only uncovered entrance is if they go through the outlook you were just in, and they'll still have to come into view if they want to shoot at Ghost or Ozone.
You can also use Ozone or Ghost's position, or just stay mobile. Regardless, just hang out and survive until it hits the 1500 mark. This should signal the last big wave. Some helicopters will bring more soldiers to the battlefield. Run back to the outlook and grab an RPG. Look out Ozone's window and aim just a little bit above the helicopter's rotor. This should bring it down and weaken the next wave.