[HELP] Snap, crackle, pop on calls?

Noticed all installations of Asterisk we have running experience a click or popping sound from time to time on calls.

Any ideas, suggestions (e.g. using VLAN with QoS is necessary to eliminate this …??)?

Thanks.

I have found the same but only when I make outbound calls over PSTN with a soft phone. Over the LAN it seems to be fine and less of a problem with the “hard” Polycom IP phone.

Puzzles me too.

Digium tech advised that allowing both ztdummy to run while a TDM card is installed can possibly lead to this as you have two timing devices competing to advise Asterisk as to timing needs.

Equally, an AAH forum user commented that he also config’s his codecs to use a 20ms jitter buffer to match the hardwired 20ms setting of the Digium cards.