How to prevent tremolo playback when using a tremolo sound

I need to include an unmeasured tremolo on a bowed-string note. According to Gardner Read (Music Notation) and Elaine Gould (Behind Bars), this requires both the word (or abbreviation) "trem." and three slanted slashes on the note. With the text properties it is possible to set the sound to a natural tremolo (which sounds pretty well), but when including the slashes, the mark forces the repetition of the notes, which is quite unnatural. So I wanted to disable playback of the slashes, but I don't seem to be able to do so from the Inspector. Most playable features such as notes, trills and so on, have a check box allowing to play or not the feature, but this is not the case for the tremolo slashes.
Is there some way to achieve this?