Double click problem

Hi
I'm have serious issue where when I click it sometimes acts as a double-click instead.
So sometimes instead of drinking one potion I drink two.
Or instead of a single attack I attack twice.
The real problem is when I use fireball spell - If it double clicks I cast fireball and after that auto attack which often times results in death.
Because of this I can't properly play anymore.
I don't have this issue in any other game or program and I didn't notice it in the free version of the game.
I'm using DD enhanced edition which I bought on GOG.
Could you look into this issue?
I'm have serious issue where when I click it sometimes acts as a double-click instead.
So sometimes instead of drinking one potion I drink two.
Or instead of a single attack I attack twice.
The real problem is when I use fireball spell - If it double clicks I cast fireball and after that auto attack which often times results in death.
Because of this I can't properly play anymore.
I don't have this issue in any other game or program and I didn't notice it in the free version of the game.
I'm using DD enhanced edition which I bought on GOG.
Could you look into this issue?