Unless the beer is a stout or some kinda of specialty beer, I carb all of my keg beers at 12 PSI for three weeks at 40 degrees. Once my beer is carbed properly, I drop it down to 8 PSI for serving.
I think you just need to give it a few more weeks. If you want to carb it faster, remember that CO2 dissolves into solution faster at LOWER temps and HIGHER PSI, but there is such a thing as TOO much carb. Put your kegorator on the lowest temp it will go above 33F, and the PSI at around 12 for three weeks, and you'll end up with perfect carb for most ales 95% of the time.