channelConfigurationIndex is 0 but channelConfigurationIndex (value) could be used for channel mapping (channel mapping)
ISO IEC 23003-3 (USAC):channelConfigurationIndex: Not forbidden but it may leads to playback issues with some players due to uncommon channelConfigurationIndex value
ISO IEC 23003-3:
Configure or update the USAC encoder in order to put a channelConfigurationIndex of (value), then reencode the content.