Multiple keyboard notes are not filtered.

I noticed that when I entered notes using my keyboard, they were registred as two intentical notes per entry. Resulting in weird selection issues. I.e. the bottom note was selected, but not highlighted.

I figured it might be due to registering the note off message, as well as not filtering the input to assure each note only occurs once. To test this I hammered one key, that did not result in more than two notes per press. however, when quickly alternating between two keys one note got registred multipple times per pitch and time point.

Version 1.2
Ubuntu 12.04
The Keyboard is a CME "u-key mobitone" in case it's relevant.

Steps to recreate:
1. Connect midi keyboard.
2. Start Musescore.
3. Create document for piano, otherwise defaults.
4. Press one midi keyboard key in note entry mode
5. Exit note entry mode, click on the just entered note.
6a. If the note is not selected, try removing it and klicking again: the bottom note was invisibly selected.
6b. If the note looks selected, remove it, a one note is left isn the same place.

Expected behaviour:
6. The note is highlighted, if delete is pressed the note is removed and nothing is left in the same spot (same pitch and time)