Brush lag

Animate CC V19, Windows 10 Pro, Intel Xoen CPU, 32G Memory, Wacom Cintiq 32. The software runs smoothly excepy after drawing 30-40 simple circles with paint brush, become extremely lag. Only show dots with pen stroke, need about 2 seconds to show the acture line. Uninstalled Animate CC and reinstalled but no help. Create a new layer or an empty frame it turns good again.

Any one has the same problem?