Well, this is how development should/can run - start over early enough to not get into a bind. So, I have decided to take a sledge hammer to my current "issues" in using the STM32F407VG as the basis for a "simple" audio effects USB device. With this, I am seeing why these devices run up in cost. Getting to the crux of my issue(s): I can either upgrade the STM32 and still sacrifice a few features...or jump to an old reliable...the IMX6 running Linux!