With the Floyd Rose, its harder to set up than a strat style tremelo or a fixed bridge. Is your intonation fairly good? Also, if your "pounding" on the strings, its possible that when you play them, your hitting them hard enough that the trem is pulling tward the bridge or they are hitting the tops of the frets which will cause a buzz, both will make the strings sound detuned. Also, if your pressing too hard on the bridge while palm mutting, that can cause a slight detuning as well.