As I said in the title, it's working as it should. If you have a low impedance source signal this passive DI is the right tool if you need it. I used Behringer and other cheap DIs in the past, and there isn't really comparison. Those were, generally speaking, much more noisy and not reliable in a couple of situations, this one just does the work instead.
Plus, the double signal pad at the input, together with the invert phase switch and the ground lift switch, make this DI very versatile for many setups I guess