If the Rotary VOLUME control doesn't work, please check if the volume adjustments can be done on your device.
Please reset the speaker by performing the following steps:
1. Turn off the HD55 and charge it for at least 30 min.
2. Make sure the AUX cable is not plugged in.
3. Go to the Bluetooth menu on your source device and delete all saved devices from the list by clicking on "Forget this device".
4. Turn off your source device then and then turn it back on.
5. Turn off the HD55 then turn it back on.
6. Switch the HD55 to the pairing mode and follow the instruction for connecting.
If the issue still persists and you want our further assistance, please click Contact Us. We will help!