Choppy call by Person calling into asterisk

I’m troubleshooting a problem with asterisk. When someone calls, I hear the person fine, however they claim that I sound choppy. Usually I ‘restart gracefully’ and it seems to clear the problem, but it always comes back. This is harder to troubleshoot, so I was wondering if anyone had any ideas on what this is. Please advise.

Peter Borghard

I assume that you are with a SIP or IAX2 service provider across the Internet? This happens because your upstream ADSL bandwidth (I’m assumign that you are on ADSL) is a lot lower than the downstream bandwidth. If you are using the default codec (G.711) then try changing to GSM or something similar. Do this by adding the following to your trunk definition:


GSM uses much less bandwidth than G.711. You could also try G.723, ilbc, or speex if your service provider supports these.

We have incoming/outgoing bandwidth variances between 0-20MB at any given time. So it’s not like I’m on a small pipe. I don’t believe as though this is a factor.

Hi Peter,

We same to be having the same problem, did you find a solution?

Regards, Cindy


There are a few things to look into. The first is your service provider. After we changed providers, we realized the problem improved significantly. VOIP is very sensetive to any network problems. So find a clean network with low ping times/latency. Also if you’re connecting to an IAX provider, see if they have an alternate proxy to connect to. Sometimes one proxy would be running slow, and I would connect to another to clear up the issue. finally is something called zaptel timing. If you’re not using hardware based Digium products, you will need a software based timing device. Zaptel provides this, however I don’t really understand the logic behind it, so I can’t elaborate.

Let me know if you have any other questions.


If you’re using a broadband connection, you might consider checking the upload speed.

Many (most) ISPs will give you excellent download speed, but will significantly throttle down your upload speed.

This is principally so you do not become a significant burden to your local neighborhood network segment by building and hosting your own website or something like that.

There are many sites you can use to check your available upload speed.