A few days ago, my cpap started blasting air during inhale

It has a recall on it which I just found about while researching this issue. I don't think the issue is related though, but in any case, I've initiatedd the proces to get a new one. But it apparently could take months, so I'm left with this issue in the meantime.

I've been using this machine for three years without a single issue. But about a week ago, my CPAP (philips respironics dreamstation), in the middle of the night, started BLASTING air into me during inhalation. Then on exhalation, it would change pressure so steeply and suddenly it almost felt like it was applying active suction. (Just describing the feeling, not claiming that was literally happening!)

It made it uncomfortable to the point of being impossible to use.

I checked all the settings, they were the same as they had always been. I went ahead and turned "c-flex" off, though (the feature that has it do a different pressure level for inhaling vs exhaling) and this seemed to fix the problem, and I learned I actually preferred c-flex off anyway.

Anyway it fixed the problem. For One Night.

The next night, in the middle of the night, it started doing the very same BLASTING behavior. C-flex was still turned off.

Even if I set the presssure lower than would be useful for me, minimizing it for example, it was STILL feeling too strong on inhale to be usable.

So right now I can't use it, unless I can find a fix or workaround. Have you experienced a similar issue? Any idea if there's anything fixable by me that could be causing it?

Mask fits perfectly, I can't detect any leaks.

Interesting related behavior--if I take a deep deep breath in, and exhale very hard afterwards, then for several breaths afterwards, the issue seems to go away. But then over the course of two or three more breaths it builds back up into the BLASTING behavior. :/

From what you describe it would appear to be a defect with the machine. Flex like EPR on the ResMed machines should reduce pressure on the exhale. A higher setting means more of a reduction. A three setting should be a reduction of 3 cm of pressure on exhale.

Machines are in short supply. You may want to check into getting a special model of the AirSense 10 AutoSet. I believe it is called the C2C model and does NOT include a wireless modem so it cannot transmit data to the cloud. I find that feature of no value to me in any case. I helped another person get one in Canada recently and they were available at a very good price of $695 Cdn. The on line vendor which does not ship to the US had good stock of them.