Message overlay when using flashlight

Hi,

in our Gear VR application (on Samsung S7), we use the flashlight to signal the state of the VR experience to a supervisor outside of the VR experience.

Everything works as expected on our main test device, but on one of our end user devices, we see the message overlay "Lampe allumée" (which means "Lamp on") within the experience. We've checked all settings but we cannot see any difference in them.

Has anyone an idea how to get rid of this message?

Thanks,
Stefan