I would say that is only true when the 808.3 is directly driving the speakers (2 channels).

Routing the ID40 data from the 808.3 to 861v6 involves transforming the audio to an SPDIF/AES signal and then converting it back again once inside the 861v6, which can introduce jitter (albeit very small).
Having the ID40 card in the 861v6 eliminates this SpeakerLink connection and the associated jitter.

For 2 channel play back with an ID40 card I would suggest in order of most optimal:

1) ID40 --> 808.3 --> Speakers
2) ID40 --> 861v6 --> Speakers
3) ID40 --> 808.3 --> 861v6 --> Speakers

Unless of course [specuation mode] the 808.3 has a better implementation of appodizing in it compared to the 861v6, which outways the downside of having to use a SpeakerLink between the two boxes.[/specuation mode]

Regards,
Carl

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