Hi All, I have obtained a Beoplay A2 first edition with supposedly a broken battery. So I swapped the battery with 2 other ones and it worked, but it doesn't charge the battery. The adapter gives 15v, the orange led is on. But when I measure the battery itself the voltage goes slowly down... I looked at the mainboard with a magnifier, but I didn't directly saw something odd like oxidation points. The power connector makes proper contact. Is there something else that I can check? I have also another A2 Active wich I can charge the batteries without problem (2 original, 1 after market.)   TIA