Tablet brush pressure issue

[argzombies]

Hey all,

Currently running a Wacom Intuos Pro with all the current drivers on Sierra. 24Gb Ram, 2.8 GHz etc etc.

For some reason, over the last few months or so, I'm experiencing a massive problem with the default PS brushes not tracking with pressure correctly, and essentially dragging different tinted circles everywhere. This issue only happens with the inbuilt brushes - example below:

Is there a fix to this to create smooth, pressure-reactive lines, or does it fully lie in just ignoring default brushes altogether?

Thanks in advance!