Cubase 8.5.1 Cue sends volume problem

Clicking the “Activate/Deactivate Cue send” button when the send volume is set to -inf brings up a window with all possible volume values and not activating the send.
This doesn’t happen when the volume is set to other values.

  1. Create any track
  2. Press the “Activate/Deactivate Cue send” either in the mixer or in the channel settings window.

Cubase pro 8.5.1
Win7 64

Confirmed. Extremely annoying.