NCurses terminal rendering breaks when data thread loop delay is short

[jamestaylr]

When transmission_delay in values is exactly less than 0.5, the terminal starts printing out gibberish output, like so:

This is most likely caused by the top screen not refreshing at a fast enough rate to keep up with the rendering in the bottom NCurses window. There should probably be configured limits on these values.

If the problem cannot be remedied in NCurses, then the terminal should drop into raw text output display instead.