iPhone headphone adapter with volume control?

Shure makes a volume adapter that comes with most of their headphones, simple about an inch long chord with just a cheap looking knob. Although it looks rather cheap in my expereince it has help up nicely. Althought with the MPA and the side volume control...I really don't know why you would ened one?

I just picked one up today at RadioShack for $10. The brand is Accurian and the plug needs just a little trimming with a knife and it will fit the iPhone perfectly. It completely eliminated the slight "hiss" that can be heard with good in-ear headphones. The only downside is the 4 foot cord, but I'll live with that tied up in my pocket.

EDIT: There is no mic on this adapter, and a set of headphones with mic will not work with it. Sorry, I didn't read the first post close enough.