the landing movement is ONE, i.e. it is not a "dud-dud" sound it is just "dud" as both feet land at the same time.
Aaaaa I understand now,that's difficult,all i can here when I do it on my bedroom floor is dy-dy.Hmmmmmmmm I'm going to have to work on that one.
What I was explaining - probably badly -
Nah you probably explained it fine,I'm sure everyone else understood.Typical me!