I don't put a lot of faith in bluetooth headphones in general. Adding the extra compress/decompress step to a weak (30 ft. maybe) signal doesn't fill one with confidence.
I don't see any giant latency issues in your results (just barely enough to notice) ... so I figure the quickest, easiest try would be a different wifi/bluetooth card. The Intel cards actually have one of the better reputations, but if you simply want to try something else as a cheap experiment (that won't make you cry if it doesn't work) ... you can give the little Realtek card a try ... heck, it's less than £ 6.26 ( £ 6.26 ( $9)) with free shipping (from China of course)
300M WiFi Card 04W3813 Bluetooth 4 0 RTL8723BE for ThinkPad E440 E540 S440 S540 | eBay
From the zillion notebooks that have passed through my repair shop, I find the Realteks to be like Toyota Corollas - maybe not sexy, but reliable & affordable.