[Problem with retraction]

Hello everybody my name is Natan and I'm having troubles with my UM2.

Since I bought it I can't have clean prints without the stringin.

I try printing in low temperatures and high speeds but I can't solve it.

Every time that I put more than 1 model it stringing everywhere.

I can see that the material is been extruded when the hotend is traveling without printing.

I show you a pic.

Please if anyone has the same problem and you solve it or any help will be welcome!!

Thanks!!