Strings Muse Sounds can't play rhythms properly

I write very heavily with strings and tend to write things with more complex rhythms. Even for more simple rhythms (like triplets), the string sections tend to drag/lag. There are unnecessary slides between notes that I don't know how to erase unless I take the second note, make it the 3rd voice, and then take the rest in the 1st voice and make it invisible. It won't even let me do that with triplets.

Sometimes I can add tenutos to the notes and it will suddenly play the proper rhythms, and other times it won't. Many times, it will only play the correct rhythms if I put marcatos or accents, which changes the sound. Sometimes two eighth notes will sound like a dotted eighth + sixteenth, and other times it's fine. Triplets tend to lag dramatically with the last one being cut off, especially at the end of the measure. In general, it seems like rhythms at the beginning/end of measures get really messed up.

I've noticed this issue primarily with the viola section, but it's affected my writing with all strings to a certain extent.

The worst part about all of this is that it's INCONSISTENT. The sounds, these problems, the playback in general is SO inconsistent. It's making the entire compositional process much longer than it should be for me, and I'm wondering if this is a problem MuseScore is working on solving? Is there a way to fix this?

I'm including a screenshot of what the viola part looks like in one of my pieces. There are times where I needed accents for the rhythms to play properly and not lag, and there are other times that are nearly identical that played the rhythm correctly without me having to fiddle with it.