That's cool, makes sense. Since I now understand that I'm dealing with a graph/display issue, maybe I need to do some heavier lifting? That is, unless somebody can suggest a better way, I guess I'll try and do block-synchronized snapshots, somehow walk/traverse the fft results myself and look for local discretized maximums. Doesn't seem like much fun...
The real truth is that although I stand to learn a thing or two by going down this road, I'm probably just reinventing the wheel and could drop in an existing spectrum abstraction or external huh?
If you're looking for locations and values of peaks in a signal block, you can use pique~ to do that. When I started out, I wrote an external called maxval~ to do this, not realising there was one in front of my face :) I recommend writing an external as an exercise anyway. Chances are, you will eventually find yourself with some function you want. It's better to space out the heavy lifting than doing it all at once