Yes, there appears to be now. I don’t know exactly when it happened, but I suspect it was some point in the last year. I can say it was NOT when they added the grey color though, nor was it when they 1st added a nozzle lip. The v2 tuning was some point long after that. Because I have a v1 grey pair with a nozzle lip (from when the grey color and nozzle lips 1st appeared) and its FR measures 100% identical to all my old v1 ones (2 black, 1 red, 1 green). But a black pair I recently bought sounds totally different than all my other ZS6, which I am not happy about at all. So something was definitely retuned, as the treble sounds different.