Pen pressure issues/inconsistency

Hi, for the past few months, it's had pen pressure issues like the photo I've put at the end. I've used the Wacom Cintique 16-inch for about a year and it's always been connected to an I-mac computer- I'm not sure of its specific model, just that it's about 5-7 years old. 

I honestly have no clue if the problem is related to Photoshop or Wacom; I've replaced the stylus tip, restarted Photoshop, restarted the Wacom driver multiple times, updated everything Adobe/Wacom related,

All I know is that it was working fine at the beginning, then had these issues on and off, and now it's a constant problem.
^ every stroke I make - the ink is super thin, then super thick with no in between