Glissando/tremolo assistance

I'm trying to have the violins do a glissando, preferably while also doing a tremolo. I'm looking for a way to have the playback do the glissando as a slide rather than play individual notes. The different playback options don't seem to work correctly, other than chromatic which plays the individual notes - the others all play the starting note and hold it, until switching suddenly to the end note. I'm new to using the software so I could be missing something in the settings. Is it possible to have the playback slide the tone smoothly? Thank you