# SRT stream does not support Dolby Audio **URL:** \ **Category:** Wowza Streaming Engine\ **Created:** [March 30, 2020, 11:04pm UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910 "2020-03-30T23:04:21Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Prashant\_Kulkarni](https://avatars.discourse-cdn.com/v4/letter/p/c57346/32.png) [@Prashant\_Kulkarni](https://community.wowza.com/u/Prashant_Kulkarni)\ **Post date:** [March 30, 2020, 11:04pm UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910/1 "2020-03-30T23:04:21Z")
I am testing SRT on Wowza Streaming Engine. The on-prem live encoder is sending srt stream with Dolby Audio in it. The Wowza Encoding Engine does not recognize the audio and gets rid of audio stream and publishes DASH and HLS outputs without audio in it. If I configure on-prem live encoder with AAC audio, it works and I see audio track as part of DASH and HLS outputs. ---
**Author:** ![Karel\_Boek](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/karel_boek/32/454_2.png) [@Karel\_Boek](https://community.wowza.com/u/Karel_Boek)\ **Post date:** [March 31, 2020, 10:23am UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910/2 "2020-03-31T10:23:08Z")
See the tech specs of Wowza Streaming Engine here: [https://www.wowza.com/products/streaming-engine/specifications;](https://www.wowza.com/products/streaming-engine/specifications;) it supports AC3 (Dolby Digital) and EAC3 (Dolby Digital Plus), is it either of these that you’re sending from your encoder? ---
**Author:** ![Prashant\_Kulkarni](https://avatars.discourse-cdn.com/v4/letter/p/c57346/32.png) [@Prashant\_Kulkarni](https://community.wowza.com/u/Prashant_Kulkarni)\ **Post date:** [April 2, 2020, 1:38pm UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910/3 "2020-04-02T13:38:13Z")
I had filed a bug related to codec signaling (Dolby audio related) which got fixed in ver 4.7.8. Last week, I have had success with UDP ingest ( by following those steps) and outputting DASH and HLS with expected codec signal. I am exploring what does SRT do? My setup is this: On-prem live encoder + SRT server sending SDR+DolbyAudio.srt (srt://IP:Port) to Wowza Streaming Engine in EC2 as an ingest. Wowza Engine packaging that .srt stream to DASH and HLS. This output doesn’t include Dolby audio. ---
**Author:** ![Rose\_Power-Wowza\_Com](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/rose_power-wowza_com/32/431_2.png) [@Rose\_Power-Wowza\_Com](https://community.wowza.com/u/Rose_Power-Wowza_Com)\ **Post date:** [March 31, 2020, 9:06pm UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910/4 "2020-03-31T21:06:00Z")
You could consider reviewing this article since you can enable passthrough as an option for your workflow and potentially have some success there. [https://www.wowza.com/docs/how-to-publish-and-play-a-live-stream-mpeg-ts-based-encoder#import-ac-3-elementary-streams](https://www.wowza.com/docs/how-to-publish-and-play-a-live-stream-mpeg-ts-based-encoder#import-ac-3-elementary-streams) ---
**Author:** ![Prashant\_Kulkarni](https://avatars.discourse-cdn.com/v4/letter/p/c57346/32.png) [@Prashant\_Kulkarni](https://community.wowza.com/u/Prashant_Kulkarni)\ **Post date:** [March 31, 2020, 9:03pm UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910/5 "2020-03-31T21:03:53Z")
Hello Karel Boek, I am aware that SRT is codec agnostic and it supports those audio codecs. Right now I am testing this: On-prem live encoder + SRT server sending SDR+DolbyAudio to Wowza Streaming Engine in EC2. Wowza Engine packaging .srt stream to DASH and HLS. When I use Dolby Audio (stereo or 5.1) to begin with Wowza Engine does not use audio and creates DASH and HLS with video only streams. If I use AAC (stereo or 5.1) with the same setup, DASH and HLS streams get both audio and video. ---
**Author:** ![Karel\_Boek](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/karel_boek/32/454_2.png) [@Karel\_Boek](https://community.wowza.com/u/Karel_Boek)\ **Post date:** [April 1, 2020, 2:20pm UTC](https://community.wowza.com/t/srt-stream-does-not-support-dolby-audio/54910/6 "2020-04-01T14:20:24Z")
Have you checked the logs? I suppose there’s some warning or error about this …