How to play multiple cameras simultaneously

I would like to know how to play multiple cameras at the same time.
I tried the next step, but I did not get what I thought.

  1. Start MxMC
  2. Select the grid playback menu
  3. Specify the playback date and time in the focus window
    -> The date and time of all the cameras on the grid are changed to be the same as the focus window.
  4. Click the play button

As a result of this operation, only the focus window will be played. However, the other windows will not be played and will not change.
If you then click the play button again, the focus window stops playing and the date and time of all the cameras on the grid are changed to be the same as the focus window.

Can not all cameras on the grid be played at the same time?

I am using MxMC 1.8.1.