[Baroninkjet]

Last year, I got RE0's and was thrilled with them. Had to boost the bass a bit, but the pristine highs make it worthwhile. Then after 4-5 months (light listening), one ear developed a pronounced buzzing when low tones were played. I got in touch with them and sent them in on warranty. It didn't take long to get a replacement pair, but the ones I got back were different. They were physically different for one thing. And they didn't sound the same. Same source, same settings, the new ones have a gravely sound on low volume lows. Like crowd noise between songs on live albums, for example, sound like record scratches. Don't notice it on high volume passages. If I turn off the eq, it goes away; but then the bass is lacking. I thought it might be a burn-in issue, but it's been a few weeks now and it's still there.
 
Any suggestions? Anyone else had an experience like this? I was considering getting the RE400's, but this whole experience has made me stop and think.
 
I appreciate any  feedback -- thanks!