In the Track view...
1. Click in the Track pane background.
2. Ctrl+A to select all tracks.
3. Choose Edit > Delete Special.
4. Remove checkmarks from everything except Clip Automation and Track/Bus Automation. Click OK.
5. Click in the Bus pane background.
6. Ctrl+A to select all buses.
7. Choose Edit > Delete Special.
8. Remove checkmarks from everything except Track/Bus Automation. Click OK.
That should do it.