roles of Video or Audio do not show "colored" in my Timeline

Hello dear forum
I'Ve watched a video from FCPX Tour and they select roles for various cameras and Audio. Unfortunately my system iMac latest software, FCPX 10.5.1 won't show the "colors" in my timeline, although in Index I can see that the files were attributed to the certain roles.
FCPX Tour convinced me that a colored timeline can help identify certain clips due to different grading etc. 

Can someone help me, why my timeline still is blue?

The colors that appear in the timeline are only audio role colors. If all the video clips have audio defined as dialog roles the clips will be blue.

I sometimes have to go and change the role manually. It does happen that on import it will be given a different role.
For example i often import sound FX that end up as music.

You'll need to set both the audio and video roles to the same colour, then they will show up how you want them to in your project.

Only audio roles show color.

If you end up disabling the audio it will show the colour of the video role, it's a general best practice (I have found personally) to make sure I set both video and audio with matching colours so that no matter the state of the clip it will show the colour you want it to.

Doug gave the perfect answer.

Hey moderator, you can close this thread, problem solved!

That's a very simplistic answer, and works well for small, simple productions. But it doesn't work for more complex projects.