AW2725DF, weird stripe of distorted pixel

Hello

I bought a new aw2725df monitor the other day and i noticed that when i set it on 360hz, a weird stripe of distorted pixels flash for a second on the top of the screen. That happens for a while and it reappears randomly. I tried another dp cable but the issue persisted. My video card is an rx 5700 xt and i use the original dp cable.   If i set the hz on 240hz the problem disappears. You can see this issue in the picture below. Is my monitor a defect?

Thank you in advance!