Sirius Sattelite Radio in 2006 Chrysler 300

My situation is as follows:

When listening to Sirius Sattelite radio installed aftermarket and working thru the Chrysler Radio AUX port the right side car speakers front and back don’t work.

When listening to AM/FM radio ALL the speakers work.

Is it the Sirius SAttelite radio unit or the Chrysler 300 radio or speakers?

Is it a portable receiver? If so, try it in another car with an auxiliary in port.