I've got a Finale 2008 file where MIDI playback and GPO 3 section strings play trills just fine (articulations with and without accidentals).

But when I put solo strings in, some play in some instruments sometimes, I'd be hard pressed to come up with a pattern.

I'm sure there are differences between section and solo strings that I don't get. For example: I see a ref. to "mono mode" being better for trills (and other stuff) in the GPO manual but I can't figure whether that's something I need to tweak or whether that's built-in.

Any advice? What happened when I went from section strings to a collection of individuals? I went back and checked and they are all notation instruments by the way.