Audio Mixers, Amps, Monitors Help! Please!!!?

Question

I hooked up an audio mixer, an amp and two monitors and I got sound after reading instructions from the MIxers manual online, and everythign was going well sound wie and all untill an extremely loud buzzing noise came out of nowhere which completely ceased when turning fof the mixer. The buzzing noise was close to a loud engine sound and I think came from the speakers. I tried changing up the speakers and the same thign happened. PLEASE HELP What am I doing wrong?!

Answer 1

check your polarity (+/-) on all cables. also check cables for continuity. buzzing sound may by a result of a faulty leads (short or no screen). set your equipment with different set of cables if you do not have a multimeter