I have tuned it...in fact here's the actual video of my second flight it sounds just fine right here.

http://www.youtube.com/watch?v=I8Ni177txPs

I checked the ignition, the plug, the carb, the fuel line (no bubbles)....

It was the next flight after this which I had a problem....at half throttle everything changed...picture this....its like your mowing your lawn and then you run into a thick pile of long grass then the mower slows down like it won't turn and then goes back to full rpm after you pass that hurdle...but my DA50 did this over and over again like it was going thru a bunch of bumps of grass.. if that makes any sense. If I kept my stick to full throttle it would die, it did this on the ground and it the air and this is when I started trying to examine if the low speed or high speed needled was too rich or too lean.

After all the checks my only choice was to send it back and explained in detail what went wrong so hopefully I can update this when I get my engine back and see what was the real problem...it can't be possibly pilot error as you can see from my flight video there was absolutely nothing wrong with it....