Put some time into getting a nice bottom D (probably the hardest note on the chanter for the beginner). If you're getting strange notes or squeaks, it is probably due to the fact that one of the holes is not fully covered. If this is happening try shifting your fingers slightly with the chanter off the knee and blowing the D note. When it finally sound a good D, try to identify which finger was at fault . It is often the same finger everytime.

You need to keep an eye on the Cnat here. Remember, for Cnat, you open the G and F# holes of the bottom hand, while these are closed for C#.