"Speaker only works when connected to the charger."に関する回答I find with my ones. If they play up. I.e … charging light doesn't come on when plugged in.. or sound not working when unplugged on usb. I put it upright on table with usb plugged in at top. And push down holding both sides. And do a slight wiggle applying pressure. It's like a bad / poor connection happening. And fixes both issues for me anyway.
"No flashing Light when charging"に関する回答Battery connection is poor. Have found this with heaps of my ones. Popped off charging board..complete with plastic surround. Wedged some rolled up paper on one side of battery to shim it on an angle. Had to lever battery with a flat blade screwdriver to allow gap to fit paper roll between the silicon and battery. Carefully aligned pins and put charging cap back on. I hope this helps others.. as it done my head in for ages trying to find issue.