Must be the AT9, if so, it is normal (there are other posts about this), it is area-dependant, because, afaik, 99 is for HD-LIL and RSNs, and I seem to recall that it also could be the way the 99 signal is combined by the dish.
So, basically, as long as you are getting the programing you are paying for (i.e. not missing any RSNs or HD locals), you're fine.