If differences in perceived volume are the only issue, it's probably not a problem. What kind of music are you listening to? A lot of music has a narrow dynamic range. Movies tend to have a much wider dynamic range, which means they can go from very quiet to deafening depending on the scene. The music might generally seem louder simply because there's not that level of variation in the signal. It's like when you're watching a TV show and then it goes to commercial and it seems like it's much louder. The commercial might not actually be louder than the peaks in the television program you were watching. It's just that the commercial is ALL peak.
Some people do run their centers a few dB above the calibrated level, so you might try that to see if it satisfies you. Also, how is the VP150 situated? You might experiment with placement to see if you can get better results. If you can get the front of the VP150 out a bit so it's not buried, it might help.
I'm sure other people will come along with other suggestions.
