Knocking on hollow bedroom door
Knocking on office window, thick glass
Door knock x5, hard hits on wood
Knocking on a glass surface in a bathroom.
Knock Gently on Thin wooden bedroom door Series
Tin can knocks over and rolls
Tapping on a window, Do da da do do
Tapping on a window or thin door X5
Knocking a toy chest, light
knocking or hitting two pieces of metal together.