If this gets clogged, water everywhere. Be careful.Okay, the latest on this is.....
I've purchased Fluval Foam Pad (2 pack) and shoved them up the drain, I've also folded up a 1-2 foot piece of air line tube and placed it under the two pads in the drain. The noise is all put gone. If the water pushed it out of the drain i'll probably put two small holes in the end of the drain and run a cable tie through it. So far so good.
The next small issue and it's much much much smaller is the trickle over into the weir. I might go get some filter wool which will soften the fall but also further polish the water.
My final issue which may not be solvable is the noise from the two pumps (skimmer and return pump)
Also, to quite the wier, raise the pipe in the chamber. The water will have a less distance to fall.