No, the MacBook is at 12:00 as well. My thought was that the amp would add boost relative to the MacBook's output if the amp was at 12:00. But I might put this up for sale anyway -- I splurged and bought one of these for $36 yesterday. I'll have to see how it sounds.

I just picked up a 3rd-hand MINT amp, with a 12VDC wall wart. When I connect my MacBook Pro's output to the MINT, turn it on, set the volume at 12:00, and plug in my Altec Lansing im716 (68 ohm impedance), the volume goes down relative to plugging the headphones directly into the MacBook...

I just bought a pair of Altec Lansing im716 for $65. I think they sound wonderful. On this board they are described as being somewhere between the Etymotic Research ER 6i and the ER 4p / ER 4s (the phones were designed and/or built by Etymotic for Altec Lansing). The 6i cost $90, the 4s / 4p...