Ah, you dont have an issue. I recreated your scene. What you are seeing is actually the directional light called “Light source”. If you add a skylight in your scene, then click the eye infront of “light source” to turn it off, you will see that the streaks goes away. You can also rotate this light and you will see that the direction of the light changes. In the first two images I got the “light source” on and off, and in the last image I have rotated it so the light comes directly in through the opening
This mean, you rock! On to digging into lights now.
