I found the other post on this site where the solution was to stop the playback. The audio is stopped, and for me Cut/Delete/Copy/Paste/Duplicate and some of the Remote Special items are all active - just the Split Delete is not enabled.
- Running on Windows 7 Pro 32-Bit, Intel i7-5820K @ 3.30 GHz
- Audacity version 2.1.3
See attached screen capture.