Mixer controls should require more than just a mouseover for scrollwheel to manipulate them

I'm trying to use the mixer to mute/solo different parts of my score. Due to the mixer having multiple entries per instrument, I find that I'm frequently having to scroll up and down through all the entries listed in it to find the voice I want to adjust. The most natural way to quickly scroll through this big list is to use the scrollwheel on my mouse. Unfortunately, you need to be very careful about where your mouse is positioned when using the scroll wheel. The Sound, Volume, Pan, Reverb and Chorus controls will all activate if you use the scrollwheel on them after simply mousing over them.

This is particularly a problem with the Sound control since if you start scrolling with gusto to quickly get to the bottom of a big list and your mouse is positioned a bit too far to the right, your attempt to scroll through the list will suddenly halt and you will discover to your horror that you've just scrolled the sound of a random instrument to a completely different voice. It would be very helpful if these controls required the user to click on them first before the scrollwheel feature was activated.