DA Problem

I have a new IR 328B DA. I just went out to the garage to start stripping the paint off the doors of my project.
I have a Craftsman 6.5 HP, 60 gallon compressor. I have it regulated at 90 psi. About 30' of line, no kinks.
The sander starts out gang busters, then slows to an almost stop after maybe 15 seconds. I wait a minute, then it happens over, and over...
The sander is oiled. (Which brings up another question; how do you stop the oil that comes out of the exhaust from contaminating the work?)
This sander may use more air than I can keep up, but that's not the problem here.
Stuck from day one...