Poor sound of moving hen

Moving hens (adult chickens) make awful noise (high-pitch ticking/clicking like high-frequency/volume clipping of poor audio recording / compression).

Maybe related to MC-1250 (Java), status: unconfirmed, works as expected.
So build that on the picture, put 40 in each and move left and right, enter the box and hear (awful sound from the right box ... make it bigger, add more to amplify the awful sound also increasing the distance it hurts ears).

P.S.: The sound reminds me of old vinyl discs (when not too loud, when the number of hen is limited and distance makes it less noisy).