Knocking in Summit County, Colorado

My husband and I were camping in the Eagle Nest Wilderness CO early June 2013. While hiking on the trail we had encountered a larger then normal amount of snow due to the late snow storms. We were a few miles up the trail from Surprise Lake when we heard a low growl. We thought this must be a mountain lion and due to the snow and inability to travel quickly we double backed to surprise lake and set up camp for the night. While sitting at the lakeside I saw a large, brownish red animal across the lake. The animal was large and appeared to be walking upright. My rational mind said its just a deer or another large animal that lives in the wilderness and disregarded what I thought I saw. Later that evening around dusk my husband and I were sitting in the tent when we heard what sounded like a knock against a tree. We looked out the tent door and didn't see anything. Again I assumed this must have been a woodpecker, another animal, or a hiker. We continued talking and heard the knock again, it was a three knock pattern, along with something that sounded like a rock against a tree. We got out of the tent and looked around. I told my husband it sounded like a rock thrown against a tree and said let me show you what it sounds like. I picked up a hard sound rock and threw it against the tree. Immediately a similar sound came back. I assumed it was an echo and I did it again. Again a similar sound came back. My husband then asked if I saw something moving up the hillside and explained where he saw movement. A large, brownish red animal was peeking out from behind the tree. The animal was swaying back and forth from behind the tree. The animal appeared to be squatted down swaying/peeking out from behind the tree. It had a large head with a large brow line, large shoulder, and nose. The nose and upper lip appeared to be a lighter color than rest of the animal seen. We took our sport camera and tried to take pictures of the animal but it was about 40 feet up a hillside. (We have a blurry picture but it appears to have a large animal head in the picture.) As we watched the animal sway back and forth we heard a large knock behind us to the left, towards the lake, then heard a knock up towards the animal we saw then back behind us. The feeling was very odd and made us feel very uncomfortable. My husband wanted to hike out but due to the late evening I suggested we stay and hike out first thing in the morning. We carry a large knife, bear spray, and a gun with us so I felt somewhat safe. It was a very restless night and first daylight we packed our bags and left. After hiking out and getting in the car to drive off we discussed what we witnessed and both could not explain what we saw. This has taught me not to throw rocks against trees! I would be willing to send the pictures we took. Two are extremely blurry due to my hand shaking, my husband took two other pictures, one you can see the head if you zoom up and the other it appears it moved.