I am using a folgertech ft 5 with single Z and Y axis and a hemera extruder, standard direct . the firmware is marlin 2.0 . When printing standard 20 mm test cube I keep getting a warning that the drive is overheating. I have set the current to 845 as recommended. I first reduced the current to 800, no improvement , then to 870 slight improvement. I am using a tmc2130 spi stepper driver . Ido not know how high to set the current? any ideas?