Status update on this and WOW are you guys going to get a laugh out of this one. Here is my last email response to them:
Hi,
I just got the headphones back today with an incredible surprise!
This is the Ultrasone website, the Pro900 page:
Ultrasone
Under the "Technical specificaions" section, it says:
Impedance 40 ohm
I just measured both drivers close to 32 Ohms! I asked for the 32 Ohm left driver to be replaced with one matching the right driver, instead the 40 Ohm right driver was replaced! Your company certainly have headphones with 32 Ohm drivers, but as the specs on the Pro900 says 40 Ohms, I don't really think these are it. This is starting to sound like a really bad joke, what are you people doing? What drivers are these? Oh, and the channel imbalance that was the original issue isn't as noticeable, but once I played a frequency test, I can clearly tell that one of the drivers, the right one, does not really respond below 40 Hz.
At this point, I am really out of ideas, so I'll just let you make a suggestion of what to do.
---
EDIT: Can somebody with a pair of Ultrasone Pro900 and a multimeter, please measure the actual impedance of these headphones. Perhaps they really are 32 Ohms and the website is just wrong... and I'm having trouble hearing out of one ear... and which ear it is changes when I put on different headphones or simply switch these from left to right.