Yes Curt is correct. I just tested it on the SD-90 and only one physical input port is routed to Midi Thru. On the SD-90 there is GM and Keyboard connector en1 and en2 respectively, however if you want en1 (GM) to drive the arranger ( exactly as if it were connected to en2 (Keybrd) - on the SD-90 there is a parameter in the midi port section to configure port 1 as either a GM or Keyboard port. ( I don't have an Audya) - however I would try turning on midi thru in the utility menu, connect to a different midi in port... and that port should be configured to drive the Audya/arranger - my reference is only the SD-90 so maybe there is something here that will create a thought process for you on the Audya.

Greg V.
Ketron SD-90 Technical and Operational Information
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