I am sorry, I am not sure what's happening? Are you unable to use Discord, or is it just not playing the call ended sound? Once you have confirmed this, let's try some troubleshooting:
Go to btu.bose.com on a computer and update your headphones software.
Try resetting your headphones. To do this place the earbuds into the charging case, plug the charging case into a wall outlet using a USB charger and wait 5 seconds, unplug the USB cord from the charging case and wait 1 minute. After that remove the earbuds from the case and try again. Clearing the Bluetooth list. To do this press and hold the Bluetooth button for 10 seconds, until you hear “Bluetooth device list cleared.”
Delete your headphones from the Bose Connect app and from the Bluetooth list on your mobile device and then repair them.
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