What is the meaning of the two digits on the screen of my WHIS device?
The left digit indicates the noise reduction. The noise reduction ensures that outside sounds are muted. Note: on the instructor's device, this digit should always be 3 and on the rider's device, this digit should always be 1.
The right digit indicates the channel. It doesn't really matter which channel you choose, but it's important that both the instructor and the rider are on the same channel. It’s possible that other WHIS users happen to be on the same channel as well and that could be disturbing. In that case instructor and rider can easily switch channels together with the result that the quality of the sound improves. So make sure that the instructor's right digit is always the same as the rider's right digit.