Breathing or mask problem after a bath room trip.

When I wake up to go to the bathroom during the night and then go back to sleep. It seem like the mask isn't allowing me to breath properly. When I check the report in the morning it shows a large cluster of apnea's for the rest of the night, Its like I'm not getting enough air. This mornings report showed a large cluster of events again. Part of it indicated Cheyne-Stokes events.I haven't seen this in 8 years.
My machine isn't going into ramp. Tonight I will be using my prior P 10 mask.
If anyone has any suggestions feel free to tell me.

P10 is an awesome mask.
(Your spell check really messed up Cheyne-Stokes)

The most obvious thing that pops into my head is that you in some way did not reattach the mask correctly.

I have been using this type mask ( N20) for over 1 year. Except for the last few day I didn't takeout it off. Those days I took it off and properly put it back on. If I sleep through the night I have no problem.
I would have thought that the ramp was acting up. but it checks out okay.