Running Selenium via jenkins on VM, screen size

I have a problem with running Selenium tests on VM. Tests are written under 1920x1080 resolution everything is OK until I run tests manually. Tests passes. The problem appear when I run tests through Jenkins. It's not a problem in my code. I dont know why but screen resolution is much lower (1032, 776). And that is the cause why buttons to test are not visible. Tests fails. Jenkins is opening by "Run slave agent via Java Web Start" and evertyhing works automatically on windows serwer. Old Selenium tests (written under lower resolution) works perfect. So the problem is closely related to screen size.

Thank you in advance.