Brush resizes with each stroke [M1 iMac Sonoma]

[susanl7866380]

iMac 24"  M1 chip with Sonoma 14.5.  PS 25.9.  This problem occured before the last release also.

I use a mouse for everything (never could get the hang of a pen),  For some reason, everytime I make a brush stroke with the mouse, the size of the brush increases or decreases.  It is driving me crazy as I have to use the bracket keys to resize after every single stroke.  I have checked all my mouse settings on the computer and in preferences but can find nothing that changes the behavior.  I disabled the graphic processor and rebooted to no avail.  The hardness of the brush does not seem to be affected.  I have used PS brushes the same way for years and can't for the life of me figure out what has changed or what I may have changed to cause this new behavior.  

Any tips, suggestions or clues as to what may be going on are most welcome.

[c.pfaffenbichler]

Could you please post screenshots taken at View > 100% with the pertinent Panels (Toolbar, Layers, Brush Settings, Options Bar, …) visible? 

[susanl7866380]

Hope this is what you need.  There were no layers in use, just the background layer.

Thanks for the response.

[c.pfaffenbichler]

What are the Shape Dynamics settings? 

Please don’t post snippets but a complete screenshot. 

[susanl7866380]

Sorry but I am not quite sure what info you need.  I assumed you want the entire shot of my screen but just in case I also sent a shot of the shape dynamics screen.

[c.pfaffenbichler]

Is the Size Jitter deliberate? 

[susanl7866380]

No it isn't.  Not even sure of its purpose.

[c.pfaffenbichler · Accepted solution]

Then why not remove it (or set it to 0)? 

[susanl7866380]

I will.  Thank you so much for trying to help.  I have no idea how the jitter got set in the first place.

[c.pfaffenbichler · Accepted solution]

Shape Dynamics are apparently locked. 

Click on the little »lock«-icon right of the name to avoid applying it to other brushes when selecting those.