I feel so embarrased but I figure this might help someone if I confess to it.

The two harnesses that connects the HU to the AOEM-NIS2 had fallen off during reassembly of my dash. I took it apart, reattached, and used some electrical tape to secure it (there are no retaining clips, but it is a firm connection).

Everything works perfectly - remote signal and all. Zero noise. Crystal clear. What a relief...

Can we just pretend this thread never happened???

BTW, now that I have it connected properly, this AOEM-NIS2 unit is really nice. It provides very clear RCA signals and enough gain right that I have my AMP almost at minimum gain and the volume is LOUD at 10 on the HU. I turned the gain to max on the AOEM-NIS2 and almost zero on the AMP - I figure that's the best way to maximize the S/N ratio.

 

Or...we can make it a sticky...