Newbie with Low D whistle question

Brand new Susato Low D arrived today. No problem reaching and covering the holes. Either I’m an idiot or there’s something wrong with this whistle. It will only sound if I barely blow, … I mean barely. My high D is 10 times as loud as this thing. This is my first Low whistle, so I have no comparison reference. What’s Up?

My first thought is look in the mouthpiece and windway and see if any packing foam or other detrius made it’s way inside.

I’ve had a Susato low D years ago, and if memory serves, it was quieter than the soprano, but not by that much.

i had one years ago returned it, its too moody with temperature, pitch would change and it is too quiet