Final Cut Text Effect Continuous

I'm needing information on editing the speed at which text come in with the text effect continuous. Thanks to someone out there I've managed to increase the duration substantially. The trouble is that for some reason the speed at which the text fades in is fast initially but then suddenly slows down till it's finished fading in. I need to know how to control the speed of the entering text and make it uniform across the timeline and not peak or decrease at some point into the timeline.