There seems to be some misunderstanding about 'enable core decoder'. There is no reason to disable it unless you never want Roon to decode under any circumstances. In general, what Roon does with an MQA stream is determined by the 'MQA decoder and Renderer' settings. If they are set fully to 'decoder and renderer' then Roon will not touch the MQA stream even though the 'enable core decode' is set to 'on'. I think that's why it's hidden away in the Advanced Settings, as you are not expected to need to touch it in normal circumstances.

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