Hey...
there's no need for that... chancellor butty boy...!!
Anyway... sometimes the sollution could be very simple, but easily missed by even some high chancellor... If you double-click on the volume icon in your task bar, click options and then properties...
Now if you set volume controls to recording you'll have a whole different set of sliders all together, and instead of mute at the bottom they have select.
Just have the select at line-in so that you have the pc 'listening' on that channel... and voila! (the volumes here are self-explanatory, higher-more sensitive)
Good luck...