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Your MERGING+NADAC is detected by the NADAC panel (if not, see this page)
Your audio stream is connected to MERGING+NADAC (on NADAC display, the source appears in white for the zone you are listening to)
and
When listening to PCM files, the audio is distorted, or the sound is muted.
When listening to DSD files, the audio is distorted or there is no sound at all (DOP)
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