JBL PRX812W User Manual

Also see for PRX812W .PRX815W: User guide Wireless setup guide

21Symptom Likely Cause What to doHum or Buzz.Improper A/C grounding,ground loops.• “Telescope” the audio ground by using an XLR/F toXLR/M adapter on one end.• Re-route audio cable away from AC power andlighting cables.Excessively longunbalanced cable run.• 8VHWKHEDODQFHGRXWSXWV LIDYDLODEOH RI\RXUmixer or source equipment to drive your PRX800Wspeakers.• 8VHD³',´ GLUHFWLQMHFWLRQ ER[WRFRQYHUW\RXUunbalanced equipment output to a balancedoutput.Improper system gainstructure.Review the Owner’s Manual for your systemsetup and adjust controls as needed.• &KHFNLQSXWVHQVLWLYLW\ JDLQ Speakers feedback andhowl when the microphonevolume is turned up.Microphones are pointedinto the speakers.Move the speakers so they do not point to themicrophone’s pickup pattern.Equalizer settings areincorrect.Locate the feedback frequency and reduce itusing the mixer EQ or an external equalizer.Excessive gain. Reduce the gain at the mixer and move themicrophone closer to the sound source.Too much low frequencieswhen playing back pre-recorded music.Recorded musicwith excessive lowfrequencies.Switch the SYSTEM EQ button to “Normal”.Speaker is unresponsive. System error may haveoccurred.• Power cycle the speaker.• Perform the Factory Soft Reset, see “FACTORYRESETS” on page 19.Section 7: Connection Types