Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The read-only voiceActivityFlag property of the RTCRtpSynchronizationSource interface indicates whether or not the most recent RTP packet on the source includes voice activity.

This is only present if the stream is using the voice activity detection feature; see the RTCOfferOptions flag voiceActivityDetection.


var voiceActivity = RTCRtpSynchronizationSource.voiceActivityFlag


A Boolean value which is true if voice activity is present in the most recently received RTP packet played by the associated source, or false if voice activity is not present.

Note: This property is omitted entirely if voice activity detection is not enabled on the source, or if the RFC 6464 extension header isn't present.

Browser compatibility

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