Not all USB sticks will work, only found one out of 5 I own worked, ironically a USB 3 Sandisk Extreme 64Gb formatted FAT 32. I see Bose reference those they have tested in the documentation, but the upfront marketing doesn’t appear to mention this.
Not all WAV files will play, they appear to need to be created at a sample rate of 44100 16bit (Haven’t checked 44100 24bit yet). Some of my existing backing tracks are double that 88200 so will need converting. Again the documentation I have seen simply states it plays MP3 and WAV, which it does but not all.
I guess this the nature of marketing depts, but I’d suggest that better up front clarity builds better long term goodwill.