I honestly don't know how to even go about figuring that type of thing out, so I don't know if i will be of much help, though I do plan on starting a review thread specifically for the AS-1's when I get them. I am thinking about starting it soon so i can ask about what suggestions people have for songs to listen to before/during and after burn in to really get a good idea of how the CIEM's perform and have changed over time.
If they are actually tuning on the go, this could explain a few things. We'll see when the others get their IEMs then. If they don't hear it as large as 4-5 dB, then we may know that it may have been retuned :p Which means mine could have been retuned before it got to me. I don't think it's a retuning thing though. I think it's more of perception.
EDIT: just checked my tracking number, my impressions arrived at Aurisonics just minutes ago.
Edited by kenman345 - 3/23/12 at 11:40am