Minor tweaks for playback speed control

- Use descrete values by making the slider 0,1,2,3 and then calculate
  the real value in percentage
- Fix checked -> value for getting range value
- Make width smaller and show the percentage to the right of the control
- Removed some logging unrelated to this task, just threw it in for fun.

Test Plan:
- Load up settings, make changes, reload app, make sure changes are
  stillt here.