In Audacity changes could be made via check boxes, sliders and/or direct input of values, depending on the function or window. The latter doesn’t work anymore since the Vivid release.
Audacity isn’t got flawlessly programmed software. At the desktop environment, there isn’t (everything is possible, so LXDE instead Enlightenment briefly loaded). A newer or fixed version as v2.0.6 (October 2014) isn’t in the repositories, and no not yet released and not even for Wily – and that, although v2.1.0 is final since 2015-03-29.