Hi Trumpet Guy, I'm Rich Gordon. What Mr. Vizzutti said is 100% true. For the most part, Chinese brass instrument manufacterers are at the infancy in building reliable playing instruments. The smaller the instrument, the more you will find inherent intonation problems with them. Try a different mouthpiece. You can also give Julius Liu a call and see about a true A pipe for it. His numbers on his Website.He's a really great guy and will be glad to help you. He stands by his products. Good Luck.