I was wondering, if I am running at the speed of sound while playing music on my iPod will I be able to listen to my iPod while running at the speed of sound? or we cant hear anything while running at the speed of sound.
1) If you were running at the speed of sound, you probably wouldn't be for long. The human body isn't designed to handle those kinds of stresses.
2) Assuming you're listening to the iPod using ear buds (in your ear) You can probably think of the air between the seal on the ear bud and your ear drum as isolated from the air you're running through, so no. You could still hear your music.
It is important to note that the air turbulence will probably create an extremely loud sound at such a high velocity. So while you may be able to hear your music in theory, in practice the music would likely be drowned out by the sound of rushing air.