Slowly at each first entry into a website

When I visit a website for the first time, I have to wait around 5sec. for the first response. That is not normal.

Maybe it is the smae problem like this > [SOLVED] Slow DNS resolution (no forwarding) when WAN is not active

and have you tried it? does it happen on all devices connected via Turris or just one? sorry for being rude but do you assume all of us have magic ball when you provide minimum information.