Troubleshooting : Erratic behaviour
Short answer
Perform a factory reset to restore the speaker to its original settings, or download the Marshall Bluetooth app to check for new firmware updates.
There can be several reasons why your Acton III speaker behaves erratically. Try these tips to solve the issue:
Perform a factory reset by pushing and holding the Media control button for more than 10 seconds.
Download the Marshall Bluetooth app and connect it with your speaker. Follow the in-app instructions to check if there are any new firmware updates to install.