Am I underpowering my Magnepan 3.6's?

My maggie 3.6's are being driven with a Levinson 334 amp (125 watts into 8 ohms - 250 into 4 ohms). While listening to the maggies at levels somewhere around 90db - 95db, I have noticed what I think is more than a dynamic compression. It's almost as if the amp is clipping or the speaker is distorting on dynamic peaks.
As an example, while listening to big band, when a trumpet section reaches 'forte' levels, the stage becomes shallow, the air is gone and the toanlity of the horns becomes scratchy, perhaps even a bit distorted.
Anyone got any thoughts? Could the maggies need more power, or do you think I'm just driving them beyond the listening level that the 3.6's are capable of?
In advance, thanks for you time and any input you have.