lulzbot taz 3 upgraded stutters

so, after I replaced the board and upgraded to the hexagon hotend on my taz 3 due to a min temp error and flashed the firmware, the printer started stuttering. It will move from the home position to the starting position in an incremental manner, and randomly stops while printing and then start again, increasing the print time exponentially. at first, it also affected the print quality, but after reflashing the firmware, the quality is fine. I have 3 videos that show different situations

Number 1 is the stock bed calibration gcode. it went fine, except for the incremental moment at the start

Number 2 is the part that I use as a test, but with different settings to go faster, but as you can see, it still took ten minutes, not one

Number 3 is the first video I recorded. it is the same file as number 2, but with the same settings as I had printed the file previously. simplify3d predicted a one minute print time as well.

after filming the videos, I reflashed the firmware. the result was a better print, but still taking forever due to stuttering. the first print in the picture, from right to left, was before the changed bed and extruder. the second one was after that, but before I flashed the firmware a second time. the third print is after I flashed the firmware again.
Can anyone help me?