This might be part of your Westcom problem, I think they added an additional frequency recently:
Westcom
What do you want to hear on the RACOM system? You should be able to hear PCSO just fine off of any of the towers in Polk County. Be aware that certain agencies are usually broadcasted only on their nearest tower (example: Altoona on the Pleasant Hill tower, Pleasant Hill on the Pleasant Hill tower, Ankeny on the Des Moines tower, etc.). Unless there is a Pleasant Hill PD car in West Des Moines and that radio pings the West Des Moines tower, you won't be able to hear PHPD off the West Des Moines tower. (see also:
question about racom)
RACOM is also going through the rebanding process on a lot of the tower sites (see here:
RACOM Issues - Polk). I'm not aware of any changes in the metro yet though.
There are a lot of people on this forum that are very familiar with the inner workings of Westcom and RACOM, maybe they can chime in.