Clef changes

Hi. Sometimes, if I have a treble staff where the notes are too low, say E2, and I feel they should be better represented by the bass clef, then I would select the treble clef and open Master Pallets> clefs, and click on the bass clef. This then replaces trhe treble clef with the bass clef. BUT when I do this the notes sound the same but they are not on the correct lines in the stave. For example The E2 in a stave with treble clef will show it, correctly, below the 3rd lower sub line. If I then change the clef to a bass one, so as to move the notes higher up, it should show the same note on the first sub line , but it does not. It shows it on the SECOND sub line, but this is the line for the note C2. See the files in the FILE INFORMATION attached.

In the 'Testing of Staff' file for the contra bass, the notes are E2. Then in the 'Cleff Changes' file I have changed the treble clef to a bass clef and the same E2 note is now shown on the C2 line.

Can you help?