XT regulators extremely leaky

Just tried my new sidemount rig for the first time. The Dive Rite regs breathe great in a flat or upright position, but as soon as I tried to go head down I almost drowned. They are extremely leaky in a heads down position, to the point of being unbreathable. I tried both regs and they are both the same. Also, I am not someone who gets uncomfortable with a bit of water in my mouth, I have just never experienced this level of leaking from any other regulator I have ever owned. Is there anything I can do to remedy this? Thanks for any help.

You might need to adjust the cracking effort. This is likely due to "case geometry fault" as described in the "Regulator Savvy" book by Pete Wolfinger. Essentially what happens is that when the regulator is in a vertical position (the axis running perpendicular to the diaphragm is in a vertical position) the water pressure difference at the diaphragm relative to the top of the exhaust valve is sufficient to open the 2nd stage valve and you get a slow leak. So your reg will be very easy to "crack" but you get a slow leak at the vertical position. (It's the top illustration of page 88 - for those who have the book).