Thank you for taking the time to post and welcome to the Bose Community.
I apologize for the trouble you've had trying to connect your iTunes to SoundTouch. Would you be able to confirm what version of Mac OS your system is using?
Due to recent Mac OS updates, iTunes has been replaced by Apple Music, resulting in the use of .xml file for third-party programs being removed. The option of connecting the iTunes library is no longer available in the SoundTouch app.
At this time, we advise looking towards using AirPlay/Bluetooth as a method of playing your iTunes music files through your SoundTouch system.
Sam F - Community Support
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