# Audio is missing from nDVR  with AAC Audio and Dolby

**URL:** <https://community.wowza.com/t/audio-is-missing-from-ndvr-with-aac-audio-and-dolby/47457>\
**Category:** Wowza Streaming Engine\
**Created:** [September 3, 2016, 5:08pm UTC](https://community.wowza.com/t/audio-is-missing-from-ndvr-with-aac-audio-and-dolby/47457 "2016-09-03T17:08:54Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Rubens\_Marins](https://avatars.discourse-cdn.com/v4/letter/r/f17d59/32.png) [@Rubens\_Marins](https://community.wowza.com/u/Rubens_Marins)\
**Post date:** [September 3, 2016, 5:08pm UTC](https://community.wowza.com/t/audio-is-missing-from-ndvr-with-aac-audio-and-dolby/47457/1 "2016-09-03T17:08:54Z")

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I am having problems with nDVR with AAC Audio. The same stream, on “Live mode” is OK.

The information regarding audio is missing from the manifest when you add the “?DVR” at the end

The problem persist, even when I enable “mpegtsImportAC3”, per stream, or in Application Settings.

Here are some output from the HLS manifest file, as you can see, the audio codec is missing

**Without DVR:**

_wget -qO - ‘[http://172.27.1.10:1935/live/Test.stream/playlist.m3u8](http://172.27.1.10:1935/live/Test.stream/playlist.m3u8)’_

_#EXTM3U_

_#EXT-X-VERSION:3_

_#EXT-X-STREAM-INF:BANDWIDTH=8345602,CODECS=“avc1.100.40,ac-3”,RESOLUTION=1920x1080_

_chunklist\_w1869645429.m3u8_

_ **DVR:** _

_wget -qO - ‘[http://172.27.1.10:1935/live/Test.stream/playlist.m3u8?DVR](http://172.27.1.10:1935/live/Test.stream/playlist.m3u8?DVR)’_

_#EXTM3U_

_#EXT-X-VERSION:3_

_#EXT-X-STREAM-INF:BANDWIDTH=6064531,CODECS=“avc1.100.40”,RESOLUTION=1920x1080_

_chunklist\_w1681468935\_DVR.m3u8_

_Test.Stream_

_{_

_uri: “udp://227.0.0.70:2022”,_

_mpegtsImportAC3:true_

_}_

_wowza version 4.5.0 (build 18676)_

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**Author:** ![Paul\_Shields](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/paul_shields/32/390_2.png) [@Paul\_Shields](https://community.wowza.com/u/Paul_Shields)\
**Post date:** [September 29, 2016, 2:56pm UTC](https://community.wowza.com/t/audio-is-missing-from-ndvr-with-aac-audio-and-dolby/47457/2 "2016-09-29T14:56:55Z")

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Hi,

The nDVR functionality does not support AC3 audio. Please see [this article](https://www.wowza.com/docs/how-to-set-up-and-run-wowza-ndvr-for-live-streaming#ndvr) showing the codecs that are supported with nDVR.

To use the nDVR functionality, the audio will need to be MP3 or AAC. Unfortunately out transcoder does not support the decoding of AC3 audio so this change will need to be at the source or at some point prior to ingesting the stream.

Regards,

Paul