As I said, try flipping the phase switch. Either you'll start hearing a lot more bass, or you don't. If flipping it doesn't help, then it's probably best to put it back.
Most of the bass in music including a most kick drum is in the crossover region (around 80 Hz), whereas movies typically have lots of bass well below the crossover. If there is a phase problem, one will notice the deficiency much more with music than with movies. Of course, movies have plenty of bass around the crossover too (lots of chest slam), so fixing a crossover phase problem can improve movies too.