I also have a tv/fm card, and a computer controlled am/sw radio
plugged into the line input.
And, the xmitter (and radio) is plugged into the power station.
In my case, what I do is simply turn the xmitter on from the power
station, set the speakers to quad, launch the whatever
outputting media app, and I'm good to go, even outside, within
reason, with any fm radio.
Thanks!