It's a very strange "problem" Guys.. I have my new Beyerdynamic's DT 990 Pro and for me, their sound is very good

But now, about something else. I've just noticed (after 1-1,5h of listening), that there is something like slightly shifted center to the right or just hm.. more lowest freq. of bass in the right earphone. I think it's not the matter of my ears because when I changed set from L-R earphone to R-L I had the same effect but now, similarly, in the left ear. But what's the most astonishing is that I have the same problem in my "old" intrathecal JBLs T100A. So, I don't think I have this bad luck to order bad copies (not to mention the quality of these brands)

Maybe this is a technology in which contemporary headphones are made ? I would be very grateful for your help production mates

!