Problems downshifting with Flatshifter Max

I seem to be having a problem down shifting with my Flatshifter Max system. Up shifting is pretty flawless, only a miss shift here and there but lately down shifting passed 4th gear has become quite an issue. Does anyone have any suggestions on what to try to fix this? Can/does that solenoid get weak over time? The system came on the car when we bought it used 3 years ago. It worked fine the first year, had only a few issues with it last year, but this year no such luck. We did install a new motor over the winter and I made sure to install the shift lever in the correct location. I do not have the funds or time to switch over to another system so that is not an option. Thanks for any help you can give.