Art.....
Use the money you'd spend on a re-titration....to buy a Respironics "M" series Auto with AFLEX and Integral Humidifier. Add "Viewer" software and a card reader. Send your original prescription to CPAP.com and buy from them.
With the new machine, you can run your own "self-titration" studies every night (if you want to).
Relegate your present machine to "back-up status".
It's astounding that "diagnosis" (hospital titration) costs more than the "cure". In effect, you do your own titration....and get the machine for free.
It ain't "rocket science". You can do it.
Gerald