I just had that the other day and I changed out my blades after trying everthing as you did and with the new blades it solved the problem. I noticed depending on humidity and other atmospheric conditions that the blades can change shape and weight also are the blades both from the same package because I have tried to use blades from different packages like after a crash and one survives then when you put the two together they are way out of wack and you cant even check tracking the vibration is so bad. If all else is good change the blades hope this helps......[:-]