Nest Labs issued a voluntary recall of 440,000 units of Protect smoke alarms in order to fix an ongoing issue with the malfunctioning Wave feature.

Nest Lab's smartest smoke detectors have been recalled by the company over a defect that can disable the alarm. The U.S. Consumer Product Safety Commission approved the recall issued by the Google-owned company so they can fix the niftiest feature in the Protect smoke alarm. The feature in question is the Wave function that allows users to temporarily silence the alerts with a simple wave gesture in non-emergency situations.

Nest, which was acquired by Google earlier this year for $3.2 billion, shipped 440,000 units of its smart smoke alarms across the US, from November 15, 2013 to April 3, 2014. The company halted the sales of the smoke alarms in April after discovering a defect in the product's Wave function. As a part of a temporary fix, Nest rolled out an automatic software update that can be applied when the device is connected to a Wi-Fi network. As a result, the Wave function will be completely disabled but will not stop other functions of the smoke detector.

"Even with the Wave feature disabled, the Nest Protect Alarm will continue to perform its essential safety functions, monitoring for increased levels of smoke and CO, and alerting users via voice alerts and Nest app alerts (if set up) as soon as there is a potential issue," a Nest spokesperson told TechCrunch.

Nest Protect smoke alarm, which was launched almost two years ago, has earned positive reviews from critics for its sleek look and its power efficient features. The device connects to a home Wi-Fi network and can be controlled via a PC or a smartphone. It detects the levels of smoke, CO, heat, light and motion and tells where the danger lies. It also gives a heads-up before turning on a loud alarm.

The US CPSC did not report any untoward incidents or injuries related to the problem. Owners of Nest Protect can avail a full refund or use without the Wave function until further fix. The latest recall does not offer anything different from what the company did in April, but it makes it more streamlined for the refund and repair process.