You can try disabling Bluetooth absolute volume to decrease the volume .

1. Open settings

2. Scroll down until you see about phone

3. Tap software information

4. Tap on build number rapidly seven times

5. Enter your screen lock if you have one set up

6. Tap the back arrow at the bottom of your screen two times

7. If there is a search option in settings search Bluetooth Absolute Volume if there is not, Tap developer options

8. Scroll until you see a setting labeled “Bluetooth absolute volume” without quotation marks.

9. Close all your apps, restart your device and reconnect to the speaker.

10. You can now use the volume keys on the speaker to adjust the volume to your preferred listening level.

Try restarting your iPhone, and king sure your device is up to date. If that doesn't work, try resetting the speaker by following these steps :

1. Start by turning the device on if it is not already on.

2. Press and hold Bluetooth and Volume Up until the device turns off.

3. Power on the speaker again.

JBL speakers do not support playing from USB devices. The USB port is for charging a device only. It provides power out only.

Have you tried using the official JBL type c cable and pressing and holding the power button for at least 10 seconds? If you have, and still haven't gotten to work try different outlet and wall adapter combinations until you get it to work.

Try putting it in the some rice. If push comes to shove, buy a new one. Water damage is not covered by warranty for whatever reason.

Just got a replacement from Harman today. Used it awhile, shut it off, used it with an aux cord, noticed the charge lights kept turning on and off randomly, now the unit will not power on. It's fully charged, fresh from the factory.