FLStudio 20 project, some VST's generate sound. Others cannot. Also, when I solo a track, it does not generate sound. Even though it will make sound when other instruments are playing. If I crank up the volume on a solo ...
FLStudio includes a wide range of plugins: generators, tools and effects. However most of these are FLStudio format only. Which means they only work in FLStudio.
If they are available as a VST or AU format ...