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Suddenly when I plug in and turn on my speaker there is a loud hiss. I’ve tried different power cables and plugging into different outlets.. The hiss is evident whether or not there is a sound source plugged in.
@townband , Steve , Unplug speaker and use the guide below to disassemble the speaker and spray switches with electro-contact cleaner and remove, spray and reseat connections to see if that gets rid of hissing. Good luck. I hope this helped you out, if so let me know by pressing the helpful button. Disassembling Behringer Eurolive B212D Power & Control Panel
A hiss or buzz in a speaker system usually indicates a poor ground at the speaker . A solder joint may have let loose so that the wires still attached but not a good ground . You’ll need to take it apart and check the grounds. Hope this helps
