Apple has disabled a group-chat function in FaceTime after users said a software bug could let callers activate another person's microphone remotely.

With the bug, a FaceTime user calling another iPhone, iPad or Mac computer could hear audio — even if the receiver did not accept the call. The bug is triggered when callers add themselves to the same call to launch a group chat. That makes FaceTime think the receiver had accepted the chat.

The bug, demonstrated through videos online , comes as an embarrassment for a company that is trying to distinguish itself by stressing its commitment to users' privacy.

"These things definitely should be caught prior to ever being released," said Dave Kennedy, CEO of Strongsville-based security firm TrustedSec.

Kennedy, however, commended Apple's quick response this week following reports of the bug by tech blogs. He predicted the reputational dent could soon be forgotten if it doesn't become part of a pattern.

"We're aware of this issue and we have identified a fix that will be released in a software update later this week," Apple said in a statement Tuesday.

Its online support page noted that there was a technical issue with the application and that Group Facetime "is temporarily unavailable."

Apple had introduced the 32-person video conferencing feature in October for iPhones, iPads and Macs. Regular, two-person FaceTime calls aren't affected unless the caller turns it into a group chat.