Collection Rate Drop-off

[Taco]

Hello,
I'm running a SS keg pot still with a trashcan as my double boiler. When I start collecting on my stripping run it comes out at about 1L/hr but somewhere between hour 1-3 it drops down to about 1ooML/hr. The ABV stays pretty steady between 45%-50%. What am I doing wrong? At this rate I figure it will take me about 36 hours to collect the rest of what I need.