Hi,
When you glide from one note to another (and have fixed operator in current timbre), fixed operator frequency also glides.
Problem is that formFrequency and nextFrequency aren't the same most of the time, so I just forced them to be in Osc::glideToNote()
If incidentally you can't hear gliding of the fixed operator (because frequencies are equal), just try changing its frequency in appropriate operator tab.
Here's the fix in the patch.
All the best,
Djordje