[M4IF Technotes] Problem in BIFS description

[Nico Oorts]

Hi,
I have a scene description containing a scene with different 
audiotracks. I describe one audiosource (pointing to an OD)  and do a 
replace commando after some time with another audiosource.  This is 
repeated for some other tracks. When I compile the BIFStext with mp4tool 
and I play the result than  the updates are played correctly (at the 
correct time). The only problem is that all tracks are internally 
playing from timestamp 0. I thought this was related with the UPDATE 
commando for the OD, which is executed at timestamp 0. I already changed 
this but without result. Some ideas?
Best Regards,
Nico Oorts
Here are the BIFS:
Layer2D {
  children [
         Sound2D {
             source DEF N0 AudioSource {
            url [ "3" ]
              }
        }
  ]
}
InitialObjectDescriptor {
  objectDescriptorID 1
  ODProfileLevelIndication 254
  sceneProfileLevelIndication 254
  audioProfileLevelIndication 254
  visualProfileLevelIndication 254
  graphicsProfileLevelIndication 254
  includeInlineProfileLevelFlag true
  esdescr [
    ES_Descriptor {
      es_id 2
      streamPriority 0
      decConfigDescr DecoderConfigDescriptor {
    objectTypeIndication 1
    streamType 3
    upStream false
    bufferSizeDB 75
    maxBitrate 0
    avgBitrate 0
    decSpecificInfo BIFSConfig {
      isCommandStream true
      pixelMetrics true
      pixelWidth 0
      pixelHeight 0
      nodeIDBits 10
      routeIDBits 10
    }
      }
      slConfigDescr SLConfigDescriptor {
      }
    }
    ES_Descriptor {
      es_id 1
      streamPriority 0
      decConfigDescr DecoderConfigDescriptor {
    objectTypeIndication 255
    streamType 1
    upStream false
    bufferSizeDB 84
    maxBitrate 0
    avgBitrate 0
      }
      slConfigDescr SLConfigDescriptor {
      }
    }
  ]
}
AT 0 {
UPDATE OD [
  ObjectDescriptor {
    objectDescriptorID 3
    esdescr [
      ES_Descriptor {
    es_id 3
    streamPriority 16
    decConfigDescr DecoderConfigDescriptor {
      objectTypeIndication 193
      streamType 5
      upStream false
      bufferSizeDB 20
      maxBitrate 0
      avgBitrate 0
    }
    slConfigDescr SLConfigDescriptor {
    }
    muxInfo muxInfo {
      fileName "voetbal_hugo_pcm.media"
    }
      }
    ]
  }
ObjectDescriptor {
    objectDescriptorID 5
    esdescr [
      ES_Descriptor {
    es_id 5
    streamPriority 16
    decConfigDescr DecoderConfigDescriptor {
      objectTypeIndication 193
      streamType 5
      upStream false
      bufferSizeDB 20
      maxBitrate 0
      avgBitrate 0
    }
    slConfigDescr SLConfigDescriptor {
    }
    muxInfo muxInfo {
      fileName "voetbal_voetbalA_pcm.media"
    }
      }
    ]
  }
ObjectDescriptor {
    objectDescriptorID 6
    esdescr [
      ES_Descriptor {
    es_id 6
    streamPriority 16
    decConfigDescr DecoderConfigDescriptor {
      objectTypeIndication 193
      streamType 5
      upStream false
      bufferSizeDB 20
      maxBitrate 0
      avgBitrate 0
    }
    slConfigDescr SLConfigDescriptor {
    }
    muxInfo muxInfo {
      fileName "voetbal_glen_pcm.media"
    }
      }
    ]
  }
ObjectDescriptor {
    objectDescriptorID 7
    esdescr [
      ES_Descriptor {
    es_id 7
    streamPriority 16
    decConfigDescr DecoderConfigDescriptor {
      objectTypeIndication 193
      streamType 5
      upStream false
      bufferSizeDB 20
      maxBitrate 0
      avgBitrate 0
    }
    slConfigDescr SLConfigDescriptor {
    }
    muxInfo muxInfo {
      fileName "voetbal_voetbalB_pcm.media"
    }
      }
    ]
  }
ObjectDescriptor {
    objectDescriptorID 8
    esdescr [
      ES_Descriptor {
    es_id 8
    streamPriority 16
    decConfigDescr DecoderConfigDescriptor {
      objectTypeIndication 193
      streamType 5
      upStream false
      bufferSizeDB 20
      maxBitrate 0
      avgBitrate 0
    }
    slConfigDescr SLConfigDescriptor {
    }
    muxInfo muxInfo {
      fileName "voetbal_hugo_pcm.media"
    }
      }
    ]
  }
ObjectDescriptor {
    objectDescriptorID 9
    esdescr [
      ES_Descriptor {
    es_id 9
    streamPriority 16
    decConfigDescr DecoderConfigDescriptor {
      objectTypeIndication 193
      streamType 5
      upStream false
      bufferSizeDB 20
      maxBitrate 0
      avgBitrate 0
    }
    slConfigDescr SLConfigDescriptor {
    }
    muxInfo muxInfo {
      fileName "voetbal_voetbalC_pcm.media"
    }
      }
    ]
  }
] # end UPDATE OD
}
AT 15000{
REPLACE N0 BY DEF N1 AudioSource {
        url [5]
          }
          }
AT 30000{
REPLACE N1 BY DEF N2 AudioSource {
        url [6]
          }
          }
AT 45000{
REPLACE N2 BY DEF N3 AudioSource {
        url [7]
          }
          }
AT 60000{
REPLACE N3 BY DEF N4 AudioSource {
        url [8]
          }
}
AT 75000{
REPLACE N4 BY DEF N5 AudioSource {
        url [8]
          }
}
AT 90000{
DELETE N5
}