JBL FLIP 5 can't couple 2 BT speakers - no audio

Hi,

I have two JBL FLIP 5 speakers that I wish to couple together in "party mode". Both speakers produce sound when used as primary speakers. But when I use one as primary (connected via BT to the audio source), and follow the procedure to couple the second one, the second loudspeaker emits a sound to confirm coupling but produces no sound. This happens whichever one of the two is primary. And I have previously used these same speakers in "partymode" without problem (even coupling 4 or 5 speakers together).

I can't find any troubleshooting help on this particular problem. Can anyone help ?