Mouse cursor issues (changes back to arrow)

[Yurdo]

I keep having this annoying issue with the cursor of my mouse. It works just fine for a while, but after few hours (usually working with PS, Illustrator etc.) there is this thing happening - if I want to resize a window, an Illustrator object, or if I move the cursor over a hyperlink - cursor changes from an arrow to a hand or whatever desired sign - but just for a second and goes back to arrow! It is highly annoying. :/

Idk the source of this problem, but I might add that I once installed a patch for Yosemite, which changes Helvetica system font for Lucida Grande. I uninstalled it though...

I use the latest MacBook Pro 13-inch with Yosemite.

Many thanks.