Type 5 or 6 is only when use a multi channel controller ie G68 / 861 etc.
The HD621, whilst supporting multiple channels is not a multi channel controller.

Type 1 is the correct initial configuration for a pair of DSP’s in a 2 channel configuration.
Then they should be customised as required.

In the case of using them with a just a HD621 (which is not a controller), they should be set to controller = Automatic or Yes.

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