Garmin 741xs to Polk PA4A XM problem

[mikelawyer]

I subscribed to SXM radio and marine weather. I receive the marine weather fine on my Garmin 741xs and can also see the SXM audio channels displayed on the Garmin too. However, the Polk PA4A is not picking up the signal from the Garmin when I select SXM on it. I see a quick message “Check Tuner” on the PA4A and then it returns the mode to the previous source, usually FM radio. Bluetooth is working on both devices and I am able to add the PA4A to the Garmin 741xs Bluetooth list. I did have XM about a year ago and it played through the PA4A with the Garmin 741xs acting as the headend and I could select and change XM channels from the Garmin. No rewiring has been done since. Any thoughts on why it is not working or the setup steps? Thanks. Mike