Playback speed issue with PCM audio

Discussion in 'HDD Media player(RTD 1295)' started by GarryT, Aug 10, 2018.

  1. GarryT

    GarryT New Member

    Hi, has anybody come across this?

    I have a few mkv files that are ripped directly from blu-ray that play at twice normal speed with the external player. This is one example. This mkv is ripped from the UK version of the Criterion release of Cat People (1942). If I pick the second audio track (AC-3) it plays normally, but if I change to the first (PCM) track, it plays back at about twice normal speed.

    Format settings, CABAC : Yes
    Format settings, RefFrames : 4 frames
    Codec ID : V_MPEG4/ISO/AVC
    Duration : 1 h 12 min
    Bit rate mode : Variable
    Bit rate : 35.0 Mb/s
    Maximum bit rate : 37.0 Mb/s
    Width : 1 920 pixels
    Height : 1 080 pixels
    Display aspect ratio : 16:9
    Frame rate mode : Constant
    Frame rate : 23.976 (24000/1001) FPS
    Color space : YUV
    Chroma subsampling : 4:2:0
    Bit depth : 8 bits
    Scan type : Progressive
    Bits/(Pixel*Frame) : 0.703
    Stream size : 17.8 GiB (96%)
    Language : English
    Default : No
    Forced : No
    Original source medium : Blu-ray

    Audio #1
    ID : 2
    ID in the original source medium : 4352 (0x1100)
    Format : PCM
    Format settings : Little / Signed
    Codec ID : A_PCM/INT/LIT
    Duration : 1 h 12 min
    Bit rate mode : Constant
    Bit rate : 1 152 kb/s
    Sampling rate : 48.0 kHz
    Frame rate : 30.000 FPS (1600 SPF)
    Bit depth : 24 bits
    Stream size : 601 MiB (3%)
    Title : Mono
    Language : English
    Default : Yes
    Forced : No
    Original source medium : Blu-ray

    Audio #2
    ID : 3
    ID in the original source medium : 4353 (0x1101)
    Format : AC-3
    Format/Info : Audio Coding 3
    Codec ID : A_AC3
    Duration : 1 h 12 min
    Bit rate mode : Constant
    Bit rate : 192 kb/s
    Channel(s) : 1 channel
    Channel positions : Front: C
    Sampling rate : 48.0 kHz
    Frame rate : 31.250 FPS (1536 SPF)
    Bit depth : 16 bits
    Compression mode : Lossy
    Stream size : 100 MiB (1%)
    Title : Mono
    Language : English
    Service kind : Complete Main
    Default : No
    Forced : No
    Original source medium : Blu-ray

    Menu
    00:00:00.000 : en:Chapter 01
    00:09:20.393 : en:Chapter 02
    00:20:58.924 : en:Chapter 03
    00:27:03.038 : en:Chapter 04
    00:32:51.970 : en:Chapter 05
    00:37:57.400 : en:Chapter 06
    00:48:20.230 : en:Chapter 07
    00:56:02.525 : en:Chapter 08
    01:00:22.035 : en:Chapter 09
    01:06:49.422 : en:Chapter 10
     
  2. Kaaron

    Kaaron New Member

    Hi !

    Same problem here !

    A mkv file from the Criterion (!) film "Ivan's Childhood" plays 2 times faster than normal... Any idea anyone ??

    Sound is also PCM like in GarryT's case...
     
  3. GarryT

    GarryT New Member

    Thank you! I was beginning to think it was just me. The problem is with the external Zidoo player and only seems to affect files with mono PCM tracks, which are fairly common with Criterion releases.

    The internal XBMC player will play the files at normal speed, but without any audio. I managed to get round it temporarily by adding VLC as an external player, which is fine, but hopefully there will be a fix for this.
     
    Last edited: Nov 13, 2018
  4. Kaaron

    Kaaron New Member

    Ok. I will try this way... Thank you !

    My problem is with a stereo PCM file with the internal player... So I think that the PCM management is just a mess... Althought I didn't try yet to go through the many possibilities of changing the audio parameters to fix it. ; )
     
  5. ntxoa

    ntxoa New Member

    Same problem when playing mkv and selecting mono LPCM using the Home Theater 2.0 app on firmware 2.0.34.

    2 channel LPCM and other tracks play correctly.

    Tried adjusting various device settings but couldn’t get the 1 ch audio to work correctly.

    Anyone know how to convert 1 ch to 2 ch?
     
    GarryT likes this.
  6. ntxoa

    ntxoa New Member

    Just got mine fixed.

    Use mkvtoolnix to save the mono pcm from the .mkv as a .mka file.

    Use Pazera audio extractor to convert and save the .mka as stereo .flac.

    Use mkvtoonix to combine the .flac and original .mkv file as a new file. Deselect the mono pcm in the original .mkv when you do this.

    Mkv with the stereo .flac audio plays at the correct speed.
     
    GarryT likes this.
  7. GarryT

    GarryT New Member

    Interesting. Thanks for the info. I'm not familiar with Pazera, but I'll give it a try.

    Hopefully this will be addressed by Zidoo at some point though.
     

Share This Page