1. I've heard that you can clean a trumpet mouthpiece through boiling it. What about the valve end caps? There are little green dots of what may be algae or something in two caps, and a film in another. 2. My 2nd slide is stuck, and has been for years. My third slide was also stuck, but somehow, I got it out without damage. Now I reguarly grease all slides that I can move. It's not exactly my fault. An instance in marching band proved this when a director was tuning the winds. She was tuning the trumpets down the line, telling us to adjust our main slide as needed. When it came down to one of the freshman, he had trouble moving his slides. One of the seniors (I'm a junior) said that the middle school director never tunes. He said an attempt at tuning would go like this at the middle school: Director: "Let's tune." Students: "Tune? What?" I took it to Sam Ash and they couldn't do anything. There is a woodwind and brass specialist there, but apparently he couldn't do anything. 3. How can I improve intonation? For the trumpets, a part in our music is so out of tune that the director told us to take it down an octave. I have a lacquered brass trumpet, and I don't know if there is lacquer on the caps and whatnot.