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If the two Jabra discs will not link with each other (pressing the link button on each does nothing), perform a factory reset on each.
To factory reset the Jabra speakerphone, simultaneously press and hold (8 seconds) the Answer call button and the End call button until "Factory reset" is announced.https://www.jabra.com/supportpages/jabra-speak-750/7700-309/faq/how-do-i-reset-the-jabra-speakerphone
- After a factory reset, must re-pair the speakerphone with the bluetooth usb adapter.