Asterisk - Ability to detect talker speaking every 2 secs

Asterisk X in ConfBridge has the ability of talkerDetection. However, this event is only detected when talker starts to speak, and afterwards, no AMI event is sent as long as talker continues to speak. Of course, another event is sent when talker stops to speak. However, what we need is a way to receive this AMI event at a regular time-difference (say 2 secs), that the talker is still speaking. Thank you for your interest.