Brushes move slowly

Just recently the brushes have developed a huge lag. There's no problem drawing/painting in Photoshop CC so it's not the tablet.

I'm running Painter 2015 v14.0.0.728 on iMac 27 16GB ram/OSX 10.9.5. Wacom intuos medium size w/current driver.

If anyone has an idea why this is suddenly happening please respond.

 

Thanks