I think the rocks (and all God's creations) do sing His praises, constantly. Think what all God's creation is made of....atoms. Molecules. All those little elements (protons, neutrons) all spinning so fast, like tops. What do tops do as they spin? They make sound, they "hum". I think, if we could hear the molecules decibel level, the sound would be greater than the greatest pipe organ! I think God hears them. I think all God's creation praise God.
Once I stood looking at my In Law's rock house, when the sun was shining and the rocks were glowing, sparkly in spots, and throwing off warmth to me. I felt that they (each rock) were singing just beyond where I could hear it. That their tiniest element, the molecules, which were spinning, caused a great sound to rise to heaven. And that every molecule in every element of God's creation was also spinning, and making music.
That was after both Larry's parents had died. I remembered Pappy (L's dad) talking about gathering all those stones in the fields everyday as he came home from the sawmill. People said he had chosen each rock shape so well that almost every stone went into the wall with no need to chip or shape it. It was his true love gift (if not to his cantankerous wife, at least to the God he knew and loved). With nearly every rock he muscled into place and cemented , he must have scuffed his hands or knuckles, and left skin there in the rock crevasses. Skin that is made up of molecules and that spun and sang the skin part of the great music, in harmony with the rock part and the mortar part and..... well. I DO get carried away!