[Fangle]

M31  --  Ordered because I do like bass in my music.  I have now been through my entire collection of ear tips as well as the entire Monster SuperTips sample pack and I have one set of silicone tips that seal.  They fit well enough that it pulls a vacuum in my ears when I remove them and I get good isolation from outside sounds.  The M31's have about 24 hours of loud listening volume as burn-in just to see if it made a difference.  After the struggle to get them to fit, I've made it to good bass but recessed mids and harsh highs.  I also see that the sensitivity is lower than any other headphones I have.  The Android phone's volume is at 3/4 when I usually have it at 1/4 for other headphones.  To describe in speaker terms it sounds like an 8" sub and a piezo tweeter.  The harsh highs make the M31's unpleasant to use.  With an iPod Nano 3G set to trebel cut EQ settings it is still enough that listening actually hurts.
 
Again, I'm not here to slam the equipment but to see what might be wrong.  These things get such good reviews I was surprised to find them unusable.  Help!
 
[edited for clarity 12-16-12 - Fangle]

 

[Fangle]

Bump after I revised the post for clarity.
 

 

[JK1]

Perhaps you should try the JVC HA-FX101? Where did you see great reviews on the M31? I seem to recall very mediocre reviews for the M31. The good reviews were for the CW31.