I got mine with the right speaker without power, so I went ahead and load them. After a while, while they are responsible, I noticed that the speaker was left sticking on the bottom. I thought he was fleeing, but it was flat paint that melted. I cleaned the sticky substance out of it and now the lower part of the left speaker is a shiny black plastic ... That's the only problem I had with them so far.
These are some amazing little speakers! The sound is surprisingly strong and when the speakers are widespread, you get more bass you expect from such a small box. I do not know why or how, but they can play in a lot more hours than advertising. On their first load (with a 2nd Gen ASTRO2 Anker 9000mAh External Battery Portable) they lasted for 27 hours, mainly on the volume of 85%. On their second charge (Charger with AmazonBasics USB 2.1 A output with industry) as they lasted over 24 hours. I have read other reviews on this product, but nobody said that. Maybe it's just my experience with them, but I am very happy with this product.
Thank you, XMI!