I think I'm having the same issue...
Here's how it went down:
I have the crossfade LP2s and think they sound really good.
I was content.
Then I was at the mall and saw there was a brookstone there, so I decided to try the M100's since they had them on display. I plugged my phone in to test my own music and I was blown away!
Amazing bass, clarity and power. Worth the money to my ears.
Fast forward to today, when I got my M100's. Same as the quotes above. They still sound clear, but bass is nearly non-existent. I have to EQ just to get a decent amount of bass...
I've been listening to them on my phone and at my pc with foobar2k with no eq. Songs played are a wide range of genres, most 320kbps.
Details:
The brookstone pair was shadow, mine are matte black.
I ordered directly from v-moda.
I'll give vmoda a call monday and see what they say.