As weikee suggest, you need to balance the blade by switch each other the blade.

Just like me, I take 4x to switch the 5 blade around in order to get the good balance. Write down the number at the fan body and the blade. Than switch opposite each other. On/off the fan and check the result till satisfied.

Another problem is, the room size is too small for the big fan. The fan need over or equal 1meter from the surrounding each wall. The Stream of wind movement not steady and Air turbulence is created. This cause the fan wobble and noise. In this case, get a smaller diameter fan.