Ok just tried the following from my radio settings and it worked fine. One thing to remember is that the Washington Station is not much for programming ( unless you add some in, I added 5 Minute Mysteries to give it a little more substance ) it is more for events, news. Where as NBC and CBS have both events and programming.
Thus when you select Washington, you may only here the music track that comes with stock, that's it. Sometimes this can give the impression at first that it does not work, however play for a bit and you will get the news\events, etc.
Anyway here are my settings that I just tested:
[GENERAL]
RadioRealism=Yes
StartCh=1
[CHANNEL]
Name=Washington
Folder=Washington
Freq=22
Antenna=01.01.1930-01.01.2000:44.16,-35.10:100000
;MusicVolumeOnNews takes values from 0.01 to 1
MusicVolumeOnNews=0.4
[CHANNEL]
Name=CBS NEWS
Folder=CBS NEWS
Freq=30
Antenna=01.01.1930-01.01.2000:34.05,-118.22:100000
;MusicVolumeOnNews takes values from 0.01 to 1
MusicVolumeOnNews=0.01
[CHANNEL]
Name=NBC
Folder=NBC
Freq=40
Antenna=01.01.1930-01.01.2000:44.16,-35.10:100000
;MusicVolumeOnNews takes values from 0.01 to 1
MusicVolumeOnNews=0.1
Edit: Just noticed you got it working, lol, good news
I will leave what I posted just in case.
RDP