I wouldnt sweat it just yet. What size is your room? Your sub is still under warranty but probably nothing wrong with it.
When you say you barely hear any bass what source are you playing, the test tones? music? movies?
I have the SVS pb 12 plus 2 and if I listen to music or watch TV usually there isnt much bass at all.
check the test tone and see how much bass you get out of it.
Also put in a DVD that has some serious bass like Gladiator, Jurassic Park, Matrix, Master and Commander or something like that and tell us if you are wowed by it.
Make sure you set the crossover correctly as well.
Is the sub placed in a corner?