This is the reason you SHOULD NOT max out the volume when you are listenning to headphone~

Take this test to determine how serious is your loss of hearing~

Can you hear THIS?

25 years can't hear above 15kHz (that's common)

Mine-max at 16kHz.......God......that's bad.....VERY BAD......
There's one guy same as as me(in the comment section below),can hear up to 18kHz
My bro (9 years old can hear up to 18kHz)

Note:Test might varies due to your sound card,speaker/headphone.To determine the max frequency your speaker
,find the youngest family member in the house and ask him/her to try this test out.

This is a good way to test your speaker out too~