Ok so here is what I have learned... according to the service manager at my dealership. He has required Ford engineers for this issue on several occasions.. he told me that there is basically one thing that causes it BUT there are a few things that cause that one thing...
So it’s evidently the audio/sync energizing timing.. the chime itself is generated by the cluster. As the ACM starts up there is a timing/handshake that hands off the audio from the cluster to the ACM. When that handshake fails that’s when you get the harsh cheap sounding chime.
The problem lies in what is causing the handshake/handoff mid-timing. There are a few things that can cause it that they are aware of .. one is voltage, evidently there is a pretty tight limit on voltage requirements in order for the ACM to take the hand off. If the ACM thinks the voltage is to low, it will “conserve power and not take the chime handoff to conserve power for essential functions like starting the car. This “power misread” can be caused by several things .. ACM wake time, cluster voltage output rise the me... etc. The other thing that causes the issue is when remote starting etc the ACM and cluster only “partially” wake to run the car during the remote run time and then shut down again, this can put the cluster or ACM in a strange state where it doesn’t properly reset and re-execute the hand off..
He said they are working on trying to figure out where the main issue stems from but it’s been pretty slow and difficult to pinpoint.