You're the first I've seen here posting about the new Hydromax - you should post some pictures and do a review!
I would make sure that your pelvic area as well as the comfort pad are good and wet to keep a good seal. I also recall reading something about the hydromax - there is a change in the relief valve at the tip that allows you to close it off completely for filling. Does the manual say anything as far as what to do to the valve after the cylinder is filled with water? Can you see the source of the air leak into the chamber? (it should be obvious with air bubbles)
Yeah, the manual says the valve is supposed to be locked when you place your package in it and prior to filling it with water. After this your supposed to unlock the valve and begin pumping. After the first pump with the valve unlocked, it loses suction.
Got mine the other day. First use everything worked well. Second use, I now know exactly what you mean. I'm not sure what the issue is, and until myself or someone figures it out I was able to get suction by inserting myself in the tube then angling it upwards. Next I'd unlock the valve and began pumping. That seems to work. Only when I had it facing downward could I not get any suction. If you come up with a full solution please let me know. I'll do the same.
I tried this and it seems to work pretty well. The manual actually says something like that. If you dont mind me asking, where did you order from? I tried to register mine at the site it told me to, and the account has been suspended or something. Makes me wonder..