I have not found anything in coding for DSP nor anything that mentions polling.
I have attached some pictures:
The first shows the internal part of the blue connector. Per Seicane I am to insert the blue plug in the factory nav and run the 4 wires to the connector in the last photo. Assuming I have the 4 wires in the proper slots of the blue connector it doesn't get me sound.
The the next two show the two RCA wires that come from the amp and go to the Southgate convertor. I think that was part of the changes I made when I install the Mediabridge but can't remember. I'm wondering if the Mediabridge wiring is the problem.
The last one shows the connector from Seicane harness that the four wires from the nav unit are supposed to be connected.
At one point I was getting sound for 10-30 seconds. Per Seicane that meant the DSP signal wasn't stable the nav unit wired in is supposed to make the DSP become stable.
I found this video and am going to try it and see what happens:
https://www.youtube.com/watch?v=5Rgnk1vfOhM