Exped Downmat owners – question

I've just picked up a Downmat UL (Medium).

When I inflate the mat, if I shine a torch behind each baffle, I can see that the down is unevenly distributed in the baffles (particularly the outermost ones).

When I hit the pad and shake it around a little, it does redistribute the down.

Have other Downmat users noticed this issue? If it's something common to all downmats then I will just live with it, however I am wondering whether this might be a defect.

For info, I've owned 4 Synmats, but this is my first Downmat.

Thanks