So, after 15 years, this has begin to happen to my Sky-Fi sat radio and factory non-nav radio AUX too... the AUX doesnt show up in list, then sometimes when I unplug the 3.5mm sat radio source cable and then plug back in, then the AUX shows up, and plays for a few seconds, then radio switches to another source (radio/cd). so odd.
I have also been having funky things happenning to my sat radio too to make me think I've needed to buy a new one after 18 years of use... so perhaps it IS just a sat radio issue and not a BMW/wiring issue. I'll have to investigate using another music source.

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I swear, my cars are like a girlfriend.
Sometimes its a rough ride, sometimes its smooth motorin'.
Sometimes she doesnt like how i treat her and sometimes i dont like how she behaves.
BUT at the end of the day, she loves it when I am inside her.

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'91 850i
'05 X5 4.4i
'09 Clubman S