Was looking at the B&O wireless stuff when I saw a deal to get 10% back on "premium audio" headphones, speakers, subs, amps & other stuff on Amazon.
It's valid through the end of the year, you need to have one of the Amazon credit cards. URL with info here:
Cut & pasting more info, I think it's stuff that needs to be sold by Amazon:
Exclusively for eligible Prime Members with an Amazon Prime credit card. Through December 31, 2017 get a total of 10% back on select premium audio products with an Amazon Prime credit card. That's an additional 5% back on top of the everyday 5% back you can earn on Amazon.com.