Pairing on Linux Mint 22 with JBL speaker doesn't work

[Oberschopfheimer]

blueman: 2.4
BlueZ: ??
Distribution: Linux Mint 22
Desktop environment: Cinnamon

• I have consulted the Troubleshooting page and done my best effort to follow.

Since a few days the JBL speaker is not paired automatically. After Linux is running and I switch on the speaker, I can see a short flash in Blueman that the speaker has been connected and disconnected again. Then I press the Bluetooth button on the speaker and double-click the entry for the speaker in Blueman. The connection is then usually established.
However, a few times I had to stop Blueman completely, switch the speaker off and on again and then restart the whole procedure.
What could I do?

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blueman_log_2024-12-31_02.txt