Turning off the heat in the humidifier seems to have done the trick. Got up this AM after no sleep interruption from rainout and there was barely noticeable condensation in the mask. Seems to have solved the problem. Thanks to everyone for the info.

Again, thanks for the info. I got a reply this morning from Respironics Customer Service who said basically the same thing as we've discussed here; lower humidifier temp, raise room temp or sheath hose. Well, I don't want to increase the room temp so last night I set the humidifier heat to zero. Th...

Thanks for the quick replies. I'm going to look in to the insulated sheathing for the hose - my provider mentioned it the other day - didn't want to go that route as, for some reason, my insurer doesn't balk at the total cost of the machine and masks but won't cover the sheathing. Oh, well, apparent...

Following is an email I sent to Philips/Remstar today. Anyone have any suggestions? Thanks ... ed ... 1/13/09 – Sent to Phillips/Respironics from their web site. "... For the past year I have had a REMSTARPLUS Series M CPAP with heated humidifier. Recently I've experienced excessive condensation to ...