I just thought of something. I don't know about the PR S1s but the Resmeds have a setting for Reminders, i.e. new mask, turn data card in, etc. that can be turned on. W/the Resmeds it just comes on the LCD screen and flashes (at least the S8s do, I can't speak for the S9s). I wonder if the PR S1s also have Reminders that can be set and maybe the Reminders when due will cause a beep, beep to catch our attention? Probably not but ....
The Respironics software engineers aren't the brightest candles on the cake but the PAPs themselves are darn good PAPs providing excellent therapy and I find it hard to believe that someone would get two or three defective PAPs in a row. An awful lot of local DME RRTs aren't the brightest candles on the cake either when it comes to many of the options provided and don't know diddley-squat about setting up the PAPs except what's on the Quick SetUp Guide. I'd be more inclined to question the setup options by the RRT if I got a second, much less a third, "defective" CPAP from them.
ResScan 3.10 - Resmed S8 ResLink & oximeter
ConTec CMS-50D+ oximeter - Philips EverFlo 5L Oxygen Concentrator
PR SystemOne BPAP Auto w/Bi-Flex & Humidifier - EncorePro 18.104.22.168