[Gate]

I received my brand new Audio Technica ATH-A900X over-ear headphones yesterday and immediately noticed something was off when I started playing music through them. The left ear cup is slightly louder (maybe 2-3dB give or take) than the right. It's not my ears as I've flipped them around and the difference is still there just on the right side, and I've confirmed this with my friend. And it isn't my DAC/amp as my other two pairs of headphones sound just fine. My question is, is this likely to go away after a nice 50-hour burn-in? Or should I have them replaced immediately? Thanks in advance, guys.

 

[NA Blur]

This is pretty common.  It depends on the tolerance for a company for the allowable difference.
 
If it bothers you and you can replace them go ahead, but the next pair may have a similar issue.

 

[Gate]

Interesting. That kind of blows, I don't want to have to mess with balance controls every time I use this pair of headphones. I'm still hoping that they balance out after running some tunes through them for a couple of days. Time will tell I guess. I wonder why this is a common problem?

 

[Gate]

Update: I've been burning these headphones in by constantly running music through them since last night with a few breaks here and there, and after about 15 total hours of music running through them so far they seem to have balanced out a bit. The left side is only slightly louder now, maybe 1dB or so. Must have been what they needed.

 

[yeahman68]

I'm gonna have to confirm this.  I have a 2012-06 model and I believe there is an imbalance as described in this thread.