Unticking the "Play" checkbox of the articulation "Muted(closed)" does not disable its effect.
When applying the articulation "Muted(closed)" (+) to note that ties to another note, only the former note will be played, and the latter is silenced.
Sometimes, this effect is unwanted (e.g. stopped horns, wah-wah-muted brasses...), but unticking the "Play" checkbox won't help.
Steps to reproduce:
1. Tie two notes.
2. Add the articulation "Muted(closed)" (+) unto the former note.
3. Play the notes and observe the effects. Only the former note should be played.
3. Untick the "Play" checkbox of it. Play again. The playback is not turned off correctly.
Add the symbol from the Master Palette rather than from the Articulation tab.