On Mute? Doesn’t Matter—Video Call Apps Could Still Be Listening In On You

In the era of video conferencing, we’re all used to muting ourselves when it isn’t our turn to speak—who wants to hear the background noise of 30 different households when going through a presentation on the company’s latest figures?

However, a new study by the University of Wisconsin-Madison has suggested that despite users being on mute, popular apps may still be listening in on their conversations, and worse still, gathering data without their knowledge.

Kassem Fawaz, an assistant professor of electrical and computer engineering, was inspired to look into the matter when his brother reported that his microphone light remained on even when he was muted on a video call. 

Enlisting the help of graduate student Yucheng Yang, the duo tested different apps and operating systems, including iOS, Android, Windows, and Mac, to see if the phenomenon was actually a widespread problem.

The verdict? “It turns out, in the vast majority of cases, when you mute yourself, these apps do not give up access to the microphone. And that’s a problem,” said Fawaz. 

“When you’re muted, people don’t expect these apps to collect data,” he added. 

To investigate the matter further, and in a more professional setting, the pair then teamed up with scientists from Loyola University Chicago to conduct a study with 223 app users, and will present their findings at the Privacy Enhancing Technologies Symposium in July. 

The first part of the study involved asking participants what they understood about the mute button’s function, with the group being split on if they already knew video conferencing apps were still accessing their microphones while on mute. 

Naturally, most said they didn’t think data should be collected when they had silenced their microphones. 

After testing the apps themselves, the team members found that all of them occasionally gathered audio data even when a user was on mute, with one popular platform even gathering information at the same rate regardless of if a user was on mute or not. 

Should devices come with easily accessible “switches” that allow users to manually enable and disable their microphones? The researchers certainly think so, though it’s unclear exactly how users would want to address this privacy concern.

“With a camera, you can turn it off or even put your hand over it, and no matter what you do, no one can see you. I don’t think that exists for microphones,” Fawaz summed up the issue.

[via TNW and University of Wisconsin-Madison, cover image via Fizkes | Dreamstime.com]