Logo appears blury

Hi,

i am doing the website for a friend`s company, facing a strange issue:

on http://frey.nummer5.de the logo appears to be blury on some screens like new laptops and retina display. i have entered the logo in the original size of 300px × 74px, so scaling via css should not be the cause.

How does it look on your machines? Any idea why this effect appears and how to solve it?

Thanks for your help.

Regards, Sebastian.