JBL PRX815XLF Owners Manual English - Page 20

TROUBLESHOOTING Symptom No sound. Likely Cause Speaker not connected to active AC power. Speaker power cable is faulty or improperly connected. What to do Verify that speaker is connected and that circuit is on. Switch on power and verify that illuminated logo is on. • Re-seat the power cable at both ends. • Substitute a known-good power cable. No sound, speaker is connected to working AC power but won't come on. No sound. Speaker comes on. No sound with microphone connected directly to the MIC input. Blown fuse. Signal source (mixer, instrument, etc.) is not active. • Replace the fuse with the specified value and type. • Take your speaker to a competent service center. Faulty cables and connections. • Check VU meters on the source mixer. • Verify that the CD/MP3 is playing. • Use headphones to verify that the instrument is actually sending an audio signal. • Disconnect and re-seat signal cables. • Replace suspected cable with a known-good cable. Microphone requires 48V phantom power. Faulty microphone cable. • The PRX800 speakers do not supply phantom power. Switch to a dynamic microphone, use a battery in the microphone (if possible), use an external phantom power supply. • Check cable. Signal sounds distorted and very loud, LIMIT LED is lit most of the time. Excessive input signal, trying to exceed the capabilities of the speakers. • Reduce the output level of the source. • Turn down the level controls on the speaker. Signal sounds distorted even at moderate volumes, LIMIT LED is not lit. Mixer or other source is overdriven (clipping). Review the Owner's Manual for your system setup and adjust controls as needed. • Check input sensitivity (gain). • Check gain structure of signal chain. Noise or hiss heard at output. Noisy Source Device. Disconnect the devices that are connected to your speaker one at a time. If the noise goes away, the problem is with the source or the connecting cable. Hum or Buzz that increases or decreases when the mixer level controls are moved. Improper A/C ground or faulty equipment connected to mixer input. Faulty cable between source equipment and mixer. Disconnect or mute channels one at a time to isolate the problem. Refer to the owner's manual of the faulty equipment for troubleshooting help. Substitute a known-good cable for the suspected faulty cable. 20