Accustic Arts Silver Line RCA,Inrerconnect burn in

Hi, greetings from Croatia.
Yesterday I installed a brand new interconnect Accustic Arts Silver Line RCA, 1.5 m, unbalanced (handmade Germany) between the preamp and mono blocks (both have tubes) and I am very disappointed. Or am I expecting too much?
The difference can be heard but I'm not sure that's an improvement.
Anybody have experience with these cables?
Do I have to keep my nerves and wait (200-300 hours) to adapt the cables into my hi-fi system?
Welcome advice from experienced audiophiles.
Thanks, Damir.