If you don’t have a leak like '''io nut''' showed above (I didn’t after 5 years of use), try to reset the speaker. Switch speaker off. Push Source and Pair buttons at once, switch speaker on and hold buttons for 10 sec and than release. Switch speaker off and on and try. This worked for me. It should work on battery or on mains. I had to do it 2x but now it works. Hope it helps.