The short answer is, the camera isn’t defective and what you see is normal. And below is why:
Sunba IR lights work in a same way as vehicle lights; you only need low beam to view nearby objects, when your camera isn’t zoomed in.
Thus, if your IR is in “AUTO” mode (this should be the default you are in), when you focus at near objects, the IR lights are half on. And when you “zoom in” and look at distant objects, the other half IR lights will be on as the high beam. Meanwhile, the low beam side will be OFF to avoid any extra light interference. In other words, you can change the focal length to adjust the IR lights.
Alternatively, you can manually control IR lights using the “presets call” method. For example, using “103+call” as a special presets code (just enter 103 in the preset box and hit either “enter” or “go to” or “call” depending on the software you use), you can turn on BOTH sides of the IR lights.
Here is a video of how to do so:
However, both sides of IR may not necessarily increase the visibility at night due to light interference. That’s why auto high beam and low beam are designed to be separate.
Another thing you can do is to change the photo sensitivity of the camera by going to the menu (95+CALL). This is a threshold that you can control. You probably want to adjust it to make it less sensitive to the streetlight (more easier to be switched to night mode under “IR Auto”),or the other way around, depending on the installation environment.