In a non-SpeakerLink then absolutely as it is only the MASTER DSP that is connected back to the processor.

I presume this is still true with SpeakerLink, but it might just work provided the DSP with the IR enabled is connect to the MASTER bank of RJ45's on the processor.

This assumes that:
The processor will still handle return comms coming into any of the RJ45's in the MASTER bank of sockets.

Try it, though I prefer to setup systems with the centre DSP as the MASTER. (I'm assuming the DSP520 is being used a centre.)

Regards,
Carl

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