GeberitDelta51 Flush Plate Chrome Matt

I got two of these because they go with the cistern I was recommended by my builders. One fitted fine, yet when you push on it to flush the water it doesn’t feel as sturdy as others I had. The other, in the bigger bathroom, is faulty. It makes a loud noise every time one goes to flush the water, both the small and the bigger button. It nearly sounds like it’s breaking apart. It’s very annoying because if someone in my family goes to the toilet at night, the noise of this flush plate would wake me up. The builders looked into it but doesn’t seem to be a fitting issue rather a faulty item.