Freq. Gain & Q disappear in GarageBand no adjustment possible.

In the latest version of GarageBand Mac, I am attempting to adjust Q. When the cursor (pointer) reaches the lower part of the screen on my laptop and leaves the color highlighted band area, Gain, Freq. and Q disappear therefore they cannot be adjusted as per instructions. Is there another way to select a band of frequencies and adjust the Q? Attempting to widen or narrow the color coded band by touchpad does not work either.

Anyone else have this problem?