jagged lines with paint brush

[kactussjack]

Novice user here.  The paint brush lines used to be fairly smooth with minimal blurring. Now they are sharp & jagged.  I have no clue how to return to the smoother lines.

Any help is appreciated.

Thanks.

[Ofnuts]

Are you using the Pencil by any chance (and by mistake)? This is the main difference between the Pencil and the Brush.