Hello, I am quite a beginner with recorder. I have one alt, and two tenor recorders, a Yamaha with one key and an Aulos keyless, both plastic. I notice that the lowest notes, especially the lowest one, is quite weak compared to the middle or high notes. I am almost sure that is not my fault: I taped the lowest holes just to make sure that they were well covered, and still, the low note has a lower volume. This is more evident with the keyless Aulos (model A211) but it is also very present with the Yamaha. Is it normal with tenor recorders? Or is it an issue with the way I blow? I tried to blow in different ways, but the note is so weak that if I blow too hard, it squeaks. Thank you for your opinions!