After investigation and creating new blank sample project replicating KLNoteViewController view hierarchy to reproduce the issue with KL.
I am able to found out the problem was the scaling issue (probably OS bug).
The problem was after you scale down below 1, for example to 0.8:0.8 and make it back to scale 1:1 after some delay the bug will occurs.
The CGRect frame value was correct but it doesn't show so when displayed, so you have to explicitly set the frame once again to make it work like it should.
Fixed #12 issue
After investigation and creating new blank sample project replicating KLNoteViewController view hierarchy to reproduce the issue with KL.
I am able to found out the problem was the scaling issue (probably OS bug).
The problem was after you scale down below 1, for example to 0.8:0.8 and make it back to scale 1:1 after some delay the bug will occurs.
The CGRect frame value was correct but it doesn't show so when displayed, so you have to explicitly set the frame once again to make it work like it should.