E46 2004 330ci SMG (SSG) Problem

My 2004 330ci has about 51K miles on it, and just recently i've noticed that the car will 'pop' out of 2nd gear (and only second gear) occasionally and then will not let me upshift or change gears until i come to a stop. It only happens when the car is decelerating and doesn't happen everytime, but it's annoying nonetheless. However, when this does happen, no warning lights illuminate and the display continues to show "2". What i have noticed though is that the SMG pump seems to run more than when the car is unlocked or when the doors are opened; sometimes I hear it turn on when the car is sitting at a light or (provided I'm driving slow enough) while the car is in motion. From these symptoms I have started to speculate that the hydraulic pump actuator isn't holding the recommended pressure in the transmission (45 BAR I think) and the pump is compensating for the loss of pressure. It seems like it would explain the increased frequency that the pump runs and the occasional neutralizing of 2nd gear, but I am not sure, only my guess as to what is wrong.
Has anyone had any similar experiences? And if so how did you fix it, and how much?

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