CNC 3020T-D Controller box noise

Had a great afternoon with my mate Matt investigating with the control box on the 3020 T-D was so incredibly noisy, initially we were convinced it was the metal grill on the back of the box

on the fan outlet, and convinced each other that putting spacers on it would solve it, it didn't, after fitting them it was still just a noisy.

Then we noticed that putting a hand or foam grip mat of it significantly reduces the noise.  After much deliberation we decided it was a crap fan and possibly not fitted properly, as outlined in the video I just posted on youtube in the fixed1t cnc playlist.