[Teraflame]

For vocals, most songs have them right in the middle, yes? For a while now the vocals have shifted to be coming from the right more and its very frustrating for me. I don't hear anything like this outside of headphones. 

 

[wuwhere]

Have you had your hearing checked for each ear? They can probably do a frequency check on them, like the frequency response of speakers.

 

[Migou67]

You have to try with different headphones and another source and you will now if is not a hardware problem with your configuration, if is not then Doctor !

 

[J W]

Could be junk in your ears, especially if you're of a certain age. 
 
 

 

[manveru]

Yeah. I recently had a similar problem. I had been noticing for a while that things which should be centered seemed like they were shifted slightly to the right, but outside of headphones everything seemed normal (in retrospect I know it wasn't though). Over one particular weekend it got way worse all at once. I completely lost the ability to hear higher frequencies out of my left ear at all and got really bad tinnitus. Went to an ENT doctor and it turns out that I had been building up earwax inside my ears for who knows how long, and my left ear had gotten to the point where it was completely plugged up.