I looked at your video again and it looked at times when you were tensioning, that the bar was close to 20 - 30 degrees above horizontal when you clamped the strings. You might want to get it to more horizontal every time.
Also notice that one time you actually push the bar down with your hand to get it level (could have been near the end of the video). This is definitely not a good thing to do.
I could have just been seeing things and if so, disregarding what I have said.
I am just trying to be helpful and not picking on you.