Argh. I just broke out the doppler, got it and myself all set up, and it was working fine, for about ten seconds. Then it stopped working. The green light is still on, not faded. I tried the headphones in another device to make sure that wasn't the problem. I turned it off, on. Off, pulled the battery, put it back in, nada. Wiggled the audio connection. Switched earphone jacks. Nada. I don't want to have to buy another. How irritating. I just wanted to check on Baby.