One explanation can be that your OMNI 50+ is part of a 5.1 system with your Omni Bar, which will make the surround OMNI 50+ left and right rear speakers act as "secondary", and Bluetooth connection is not possible to secondary speakers. To use the OMNI 50+ as a portable speaker again, simply perform a reset of the speaker by pressing the reset button for 5 seconds. Please note that after resetting your OMNI 50+, it is no longer part of the 5.1 wireless system.