I have had the same issue as you. I too switched this year. The pressure runs away. Even while I'm woke. I look over and the machine is slowly creeping up.
No matter what I set it to...within 20 - 30 minutes it maxes out. I've have complain and complain, but I've have been lead to believe I'm the only one experiencing this
issue. But I know this is not true. Resmed company themselves were no help. My AHI are always over 3.0 and DME are no help. I think this may be an issue for people with low settings. Before I got this new machine my setting was between 7 - 8. Everyone is telling me to put it on 7.5, but it's not working.