Cannot select keys and audio tracks at the same time

Cannot select keys and audio tracks at the same time

1. Open any project with audio clips (QAGame, for example)
2. Create a sequence
3. Add a camera track and some static meshes
4. Add a few random keys throughout the timeline
5. Add an audio track with and audio clip
6. Try to select some of the keys and the audio clip at the same time (Marquee select or Shift+Click)

Result: Only the keys are selected.
Expected: Both keys and audio track are selected and can be manipulated at the same time.