idlemarvel
Neither idle nor a marvel

Thanks for your update. I will try same as you with XL decoder (instead of M decoder) again.To recap... yes control via SUSI does work, both in Function Key operation and CV programming using the CV's allocated to the SUSI banks of CV's, tested and verified using the PIKO DCC System and the Massoth Programmer, and both templates work as they should.
Below in the picture, M Decoder to S Decoder via SUSI cable, quite why an XL Decoder has so much trouble, will have to refer that one to Massoth for an answer.
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