One thing to note is that some stations are using separate DA for IBOC which causes even more pattern inconsistency. In the Buffalo area some of the stations on the Rand Building in downtown have good HD to the North of the city but not much South. From the South of Buffalo 102.5, 94.5, 99.5 (these 3 are 110KW stations) have rock solid HD everywhere except in downtown. Multipath is one reason, but there are 3 stations coming off the Rand that overload everything, analog and HD.