zebra phone glitch

I have gotten the finger scanner paired with a MyCheckout device and can make it beep using the scanner control app. I can't get it to scan while using the MyCheckout app and line-busting. Has anyone gotten that to work?

So we are getting a number of my devices with a slash across the microphone as shown in the picture. Can't figure out how to fix this but it is creating a problem where the only way we can hear the caller is by putting them on speaker phone. The zebras are not muted at all. You can hear them...