Pleasure in practice

Question: I move faster in certain solids, but slower in certain gases. I am typically broken by objects with large masses. I can be used as for pleasure, practice, and even an alarm. If used excessively, I can cause harm. What am I?

Question: What tastes better than it smells?

Question: What goes in the water black and comes out red?

Question: What asks but never answers?

Question: I have 6 faces and 21 eyes, but can't see a thing. What am I?

Question: What cannot be seen or felt, but can only be broken by voice?