Have you ever....

[METALMICKY]

I hate it. In my mind I have a smooth mid-Atlantic brogue. In fact I sound like a slow-minded Cockney!

When i first watched the video of me making a speech at a friends wedding i was amazed that i sounded like a dozy cockney

 

[Deportivo Seagull]

It has to do with bandwidth .... human hearing goes from a couple of hz to about 15khz (babies can apparently hear upto about 20Khz), however phone systems work on 15hz(?) to 3.5khz with no apparent ill effects, however because its such a small part of your hearing range your voice will seem 'dead'. Recording systems use a similar frequency range hence the crap sound of your voice.