Steps to reproduce:
1. Download the attached project and open "boot" scene
2. Enter play mode and wait until a new scene is loaded
3. In the top left corner, will be displayed Timelines info. Notice that the delay is ~2s
- In the Standalone player, the delay is ~0.05s. Similar delay is present when testing on low-end hardware (surface 3)
- In the Xbox One player, the delay is ~5s

Alternative reproduction steps:
1. Disable cycle Waster script
2. Enter play mode
3. Before the new scene is loaded open any menu in the toolbar
4. Wait for ~10s. close menu by focusing the Game window
5. When new is is loaded notice that the Timeline is delayed 20s or more.

Results: Player lag or unstable frame rate can delay the Timelines start when Timeline is using DSP Clock as an update method

Reproduced with: 2019.3.0a11, 2019.2.0f1, 2019.1.12f1, 2018.4.5f1, 2017.4.30f1