Results 1 to 2 of 2

Thread: AC3 audio hiccups/interruption at the start of every chunk

  1. Default AC3 audio hiccups/interruption at the start of every chunk

    We've got some VOD content encoded with h.264 and AC3, and it plays over HLS through Wowza. However, the audio has a tiny hiccup at the start of every chunk. It's noticeable enough to be annoying, the audio just stops for a split second, then continues. Checked the logs, nothing but the normal connect, create, play events.

    When playing the file directly from disk, the audio is fine. It's quite obvious that this hiccup happens at the start of the chunk; changing the chunk size also changes the interval between the hiccups. With a keyframe interval of 2 secs in the file, we've tested with chunkDurationTarget of 2000, 4000 and 8000. And the hiccup thus appears every 2, 4 or 8 seconds.

    File information from ffprobe:
    - Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv), 640x360 [SAR 1:1 DAR 16:9], 1202 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
    - Stream #0:1(eng): Audio: ac3 (ac-3 / 0x332D6361), 48000 Hz, 5.1(side), fltp, 384 kb/s (default)

    File information from Wowza's access log:
    - H.264 Video info: {MediaCodecInfoVideo: codec:H264, profile:Main, level:3.1, frameSize:640x360, displaySize:640x360, frameRate:23.980000}
    - AC3 Audio info: {MediaCodecInfoAudio: codec:AC3, channels:6, frequency:48000, samplesPerFrame:1536, objectType:2}

    Please contact me in case you want to test this, I can provide you with a test URL directly to the HLS stream.

    - Ubuntu 14.10 Server
    - Java 1.8.0_31
    - Wowza 4.1.1 build 13180

  2. #2


    Hi there.

    Can you please open a ticket for this issue. Please include the usual zipped /conf and /logs folders as well as the content with the issue for testing purposes. Also include a link to this thread as reference.

    Thank you.


Similar Threads

  1. AC3 Audio
    By MonkNoiz in forum AddOn: Transcoder
    Replies: 7
    Last Post: 09-26-2016, 10:04 AM
  2. nDVR and stream interruption
    By Priority1 in forum AddOn: Wowza nDVR
    Replies: 3
    Last Post: 01-07-2016, 10:57 AM
  3. Unable to import AC3 audio from MpegTS udp on Wowza Streaming Engine 4
    By f.hernandez.b in forum Live Streaming and Encoders
    Replies: 6
    Last Post: 11-11-2015, 12:41 AM
  4. FMLEcmd cannot reconnect to Wowza after interruption
    By saxonytv in forum Live Streaming and Encoders
    Replies: 2
    Last Post: 01-23-2015, 06:54 AM
  5. Audio (AC3) from hw transcoder not recognized (worked in 3.6)
    By karelboek in forum Live Streaming and Encoders
    Replies: 1
    Last Post: 03-10-2014, 10:54 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts