(value) is used but the
usacElementType sequence contains
(channel config order), which is the configuration indicated by
ISO IEC 23003-3 (USAC):
channelConfigurationIndex: "determines the channel configuration [...] Channel configurations, meaning of channelConfigurationIndex, mapping of channel elements to loudspeaker positions"
ISO IEC 23003-3:
If ISO/IEC 23003-3:2020 compatibility is expected, configure the encoder to use a value not listed as reserved in ISO/IEC 23003-3:2020, else contact the conformance checker developer in order to get an updated version.