Hi, usually if we hit the shuttle it will produce sound like 'POK!!' right? But when I hit the shuttle the sound is ' Tanggggg ' like a steel sound (I don't hit the frame) , I use I've just bought racket strung with BG66 at 27lbs (the stringer said its an old machinr so if I string it 25 it'll be very low tension), The racket brands isn't famous, I think you never heard " Toalson " brand don't you? so do you know what is the problem? is it to high tension?