Agree.I don't have a third gen MDX, but I will take a shot......Maybe the driver2 audio memory setting is set to the XM preview channel. Has she tried manually (not the presets) changing to other XM channels from the preview channel?
Have her set some presets with her key.
With us, it went to the source and station last in use.
Alternatively, you may want to reset the keys (it's in the manual) if nothing else works - the car could be confused and thinks your wife's key is a "guest" key.
Just noticed this a week ago when I had to use driver2 keys for the first time in 2.5years.....all my XM were on preview, thought my subscription ran out, lol.Are you saying two keys could have two different sets of radio channels?