As the OP's have said somethings in your skills can have an affect, also the 2% attack speed makes a difference. I dont know if it applies to both weapons or just one (id assume its both, otherwise it would just lower the attack speed on the actual weapon.)
With that 2% attack speed increase you are now hitting every 1.4 sec instead of 1.43 seconds. Same thing with your off-hand. It would now hit at 1.27 speed instead of 1.3. While the numbers done seem that different it does make a difference.