What You'll Need
- Your JBL PartyBox 310
- A known working microphone with a 1/4-inch cable
- A known working guitar with a 1/4-inch cable
- A separate, known working amplifier or speaker (for testing)
Troubleshooting Steps
- Test Your Equipment First: Before blaming the speaker, confirm your microphone, guitar, and cable are working. Plug them into a different amplifier or speaker to ensure they produce sound.
- Check Physical Connections: Ensure the 1/4-inch cable is pushed firmly and completely into both the speaker's input jack and your microphone or guitar. A loose connection is a common cause of failure.
- Adjust the Gain and Volume Knobs: The PartyBox 310 has dedicated gain knobs for each input, located right next to the jacks. If the gain is turned all the way down, you won't hear anything. Turn the gain up slowly. Also, make sure the main volume on the speaker is at an audible level.
- Verify the Mic/Guitar Selector Switch: Input 2 has a selector button that switches between microphone and guitar modes. Press this button to match the instrument you have plugged in. The mode is often indicated by a small light.
- Restart the Speaker: A simple power cycle can fix many software glitches. Turn the PartyBox 310 off, wait for 30 seconds, and then power it back on.
- Use the JBL PartyBox App: Open the app and connect to your speaker. Check for any input-related settings or volume controls within the app that might be muted or set too low.
- Inspect the Input Port: Use a flashlight to look inside the 1/4-inch input jack on the speaker. Check for any visible debris, lint, or bent pins that could be preventing a solid connection. If you see debris, try to carefully remove it with a non-metallic tool like a wooden toothpick.
- Factory Reset the Speaker: If software is the issue, a reset will restore default settings. With the speaker on, press and hold the Volume Up (+) and Play buttons together for about 10 seconds until the speaker reboots. Note that you will have to re-pair your Bluetooth devices.
- Professional Repair Needed: If you've tried all the above steps with known working equipment and the input still fails, the port itself has likely failed. This could be a broken solder joint or a faulty component on the input board, which requires professional service to repair.