Yeah im certain the difference is REALLY APPARENT. My right earpad has the boom in the bass while my left earpad like....erm flat. Dats why i always wonder why some reviewers said the HM5 is slightly to the bass side abit and i myself totally dont feel that way at all hmmm.... issit burning in? Im attempting to burn in my Left earpad with bass songs now hmm
Sorry to say this but that won't help ......if its really bad then doing a warranty claim might be the best bet , I was able to get my HM5 without any problems , all the best !