SRS-XB12

I have a pair (to get stereo sound) of Sony SRS-XB12 speakers that are over 6yo, and they still sound crystal clear with a battery that lasts for many hours. I use them daily with the TVs in my dorm and living room, and sometimes to hear music around the house. I absolutely love their well-balanced sound, so my next ones will be Sony as well for sure. I wish the battery could be replaced.

Don't know about headphones but I've taken Sony Bluetooth speakers in the sauna for years with no issues. Anything in the SRS XB range are probably fine. A friend of mine had another brand speaker that looked really similar, same rubber case, same shape and size, same cover over the ports and same buttons. I recommend that they try it in the sauna. It broke the first time.