# HLS Playback Start Time: RTSP vs MPEG-TS source stream

**URL:** https://community.wowza.com/t/hls-playback-start-time-rtsp-vs-mpeg-ts-source-stream/44439
**Category:** Wowza Streaming Engine
**Created:** [December 16, 2014, 11:29am UTC](https://community.wowza.com/t/hls-playback-start-time-rtsp-vs-mpeg-ts-source-stream/44439 "2014-12-16T11:29:56Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![1111](https://avatars.discourse-cdn.com/v4/letter/1/71e660/32.png) [@1111](https://community.wowza.com/u/1111)
#### Post date: [December 16, 2014, 11:29am UTC](https://community.wowza.com/t/hls-playback-start-time-rtsp-vs-mpeg-ts-source-stream/44439/1 "2014-12-16T11:29:56Z")

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Hello,

I’m using startMediaCasterStream() to dynamically connect to a set of streams that are then re-streamed with HLS.

I’m noticing big playback start time differences between an RTSP and an MPEG-TS source: it takes around 0.5-0.7 seconds to connect to the MPEG-TS stream and between 4-15 !! seconds or the RTSP source

The intervals above are the time between the startMediaCasterStream() call and the time the streams appear as published (logged in a custom module), so before the actual HLS segmentation begins (the final playback start time would be this time + at least 2 x chunk target duration, in my case 3000).

Is this caused by transmuxing or are there some options to be tweaked in order to speed up the playback start time? I tried disabling the jitter buffer, packet sorting etc. but it doesn’t seem to affect the start time.

Thank you for any suggestions/ideas.

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### Author: ![1111](https://avatars.discourse-cdn.com/v4/letter/1/71e660/32.png) [@1111](https://community.wowza.com/u/1111)
#### Post date: [December 16, 2014, 5:08pm UTC](https://community.wowza.com/t/hls-playback-start-time-rtsp-vs-mpeg-ts-source-stream/44439/2 "2014-12-16T17:08:30Z")

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Ok, I sorted this out. By default the AVSyncMethod for RTP is senderreport. RTCP ports were unreachable so it tried to get a SR multiple times before giving up, hence the wait time.

Turning off the StreamValidator further reduced the time.

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### Author: ![sal\_jefferson](https://avatars.discourse-cdn.com/v4/letter/s/6de8d8/32.png) [@sal\_jefferson](https://community.wowza.com/u/sal_jefferson)
#### Post date: [February 12, 2015, 7:31am UTC](https://community.wowza.com/t/hls-playback-start-time-rtsp-vs-mpeg-ts-source-stream/44439/3 "2015-02-12T07:31:39Z")

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Thanks for the update and glad to hear you sorted this out.

Regards,

Salvadore