Windows 7: How to adjust microphone / line in volume levels

During my first attempt at recording audio from a microphone line in feed... i went to control panel / hardware and sound / manage audio devices / recording / microphone/line in / levels and changed the microphone line-in volume.

My audio recording program (Adobe Soundbooth) shows left and right channel input ... i noticed both left and right channels were spiking... i went back into the recording levels and lowered the volume... some how a weird up down arrow appeared near the volume button (where you click to mute) and when i moved the mouse it changed the volume

now Adobe Soundbooth registers the left input higher than the left... and i can't find where to fix this... ideally i would like to know how to control left and right inputs individually... however... just to resolve the issue... if any one can tell me how to reset recording levels to default... that would be great!

My system is Dell M6500 mobile workstation i'm using the pre-packaged soundcard which uses IDT HD Audio drivers.

Thanks