This is probably happening because "Enable overlays for Transmit" is turned on. You can find this by clicking on the wrench menu in the Monitor, then going to Overlays > Overlay settings. In that window, uncheck the checkbox and click OK.
When that setting is on, the overlays are "burned in" to the video signal so that they are visible on any transmit monitors, since that's the only way to make that work. The scopes thus reflect that as well.