jammin is NOT okay, man. (filament regularly jams in heat break)

This is an ongoing problem with my VC 3.1 x 400. Filament gets jammed in the heat break and the only way I can get it to print again is usually to ram a hot metal rod down the filament path.
A recent rebuild of the print head (Eva 3) cleared it up for a few days, but it has now resumed being a PITA.