How to scan channels fast

Hello everybody,

I’m employed an algorithm for scan channels, but I just want to scan one channel as fast as I can. I read that the formula to get the minimum time is:


The thing is that I set in X-CTU, SD=1 and SC=1. With that values the result in the formula is 30,72[ms], but I’m getting scanning about 3 seconds of delay. The questions is, what is missing?? I’m okay?? Is my XBee dead or sth? Why I’m not getting values each 30,73[ms] ?