Changing dtmf detection interval


The system that I am running is detecting DTMF tones perfectly.

However, I realised that some users that dial into my IVR seem to have the behaviour of pressing the same key more than once in a short duration of time. I noticed that Asterisk queue each entry and execute all detected dtmf key one by one in a queue.

My question is, can I set a duration that say in every 500ms, the system only take one count of the DTMF key detected even if the key was pressed several times within that time frame?

Thanks in advance for your attention on this.

Ideally I would like to disable or clear the dtmf queue in asterisk within a certain time.

Can anyone tell me how to do this? Urgent help needed. Thanks.