# One Way Audio outgoing/incoming

**URL:** <https://community.asterisk.org/t/one-way-audio-outgoing-incoming/34675>\
**Category:** Asterisk Support\
**Created:** [March 29, 2011, 2:20am UTC](https://community.asterisk.org/t/one-way-audio-outgoing-incoming/34675 "2011-03-29T02:20:33Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![system](https://global.discourse-cdn.com/asterisk/original/2X/4/475d0c889911cfb84ac4881ad6df8b523e3f9105.png) [@system](https://community.asterisk.org/u/system)\
**Post date:** [March 29, 2011, 2:20am UTC](https://community.asterisk.org/t/one-way-audio-outgoing-incoming/34675/1 "2011-03-29T02:20:33Z")

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HI ALL!

I am having an issue with one way audio. Sometimes if I (or my customers) am called or make a call the person on the other end cannot hear me. If I hang up and call back, it seems like it works most of the time. This happens 3/5 calls made. I have ran a trace with agi debug on, sip debug on, and core set verbose 9 all to the full log. Any Ideas??? Any help would be greatly appreciated.

Running asterisk 1.6

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**Author:** ![bmj](https://sea1.discourse-cdn.com/asterisk/user_avatar/community.asterisk.org/bmj/32/453_2.png) [@bmj](https://community.asterisk.org/u/bmj)\
**Post date:** [March 29, 2011, 1:55pm UTC](https://community.asterisk.org/t/one-way-audio-outgoing-incoming/34675/2 "2011-03-29T13:55:32Z")

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This type of issue is frequently caused by an overly aggressive firewall. Are the phones, server or SIP provider currently separated by a firewall? If so, check the configs of that firewall to make certain you are allowing the proper ports of UDP or TCP traffic and that you’ve got “SIP management” features such as SIP ALG turned off.

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**Author:** ![system](https://global.discourse-cdn.com/asterisk/original/2X/4/475d0c889911cfb84ac4881ad6df8b523e3f9105.png) [@system](https://community.asterisk.org/u/system)\
**Post date:** [March 29, 2011, 3:05pm UTC](https://community.asterisk.org/t/one-way-audio-outgoing-incoming/34675/3 "2011-03-29T15:05:50Z")

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Our servers are in a datacenter directly connected to the internet pipe. Nothing between them whatsoever.

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**Author:** ![david55](https://avatars.discourse-cdn.com/v4/letter/d/e19adc/32.png) [@david55](https://community.asterisk.org/u/david55)\
**Post date:** [March 29, 2011, 3:46pm UTC](https://community.asterisk.org/t/one-way-audio-outgoing-incoming/34675/4 "2011-03-29T15:46:05Z")

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In that case, your datacentre has serious security problems!