Regulator drifting

[Bussy]

I got a kegerator conversion kit from Beverage Factory at Christmas 2011. Finally built the kegerator in August 2012. System worked great until December 2012 when the pressure started drifting on its own. I'll set it for 6 psi and within a few hours it's 15 to 20 psi and rising. Can't afford a brand new double regulator right now and frankly should not have to after only 6 months use. Anybody else seen this? Can these regulators be rebuilt or adjusted? Appreciate your input.