The volume is very smooth, although the mute can be somewhat sensitive at times (it has a touch sensor like in some lamps, etc.)

The other complaint is that the touch sensitive mute on top of the "hockey puck" control is a bit too sensitive for me

All i do Is just hit the snazzy mute (touch sensitive) and its the hissing is gone, nothing to not buy them over.

The volume/headphone jack/second audio source/mute control disc is a really nice touch too