I was using my Mackies as usual this weekend but about 4 or 5 times throughout the function one of the speakers started making a loud humming/interferance noise that lasted about 5-10 seconds each time. This happened on one occasion when no one was dancing so before anyone says it wasn't a pacemaker interefering! Any feedback would be greatly appreciated. Thanks

Make sure the IEC out is plugged into the same outlet as the other speaker, and mixer, if this doesn't fix it, and you do find the problem, please tell us, as I have had this problem for 12 months or more, had to buy some more speakers and amps to overcome it, as I can't work it out, the speakers have been serviced (three times !), thought I solved the problem last week, but it happened again, so am trying again today !

they were all plugged into the same extension socket so I don't think it was that. I was thinking it might have been because I had everything running from one socket as thats all they had in the hall, so i had 3 lights, speakers, cd players, mixer & radio mic all plugged in and I hate doing that. Might plug it in at home for a bit and see if it happens again. If I find any solutions I will let you know! thanks.

Bet it won't happen until you plug ALL your kit in, I have tested everything, brought all new cables etc, and it only happens when all kit is set up.

Let us know.

might not of been your kit... could have been a fridge or somthing on the same ring main......

its going to be a hard one to track down....

Hmmm, if it happens at a different venue then I'd start suspecting the gear.

Until then, I'd suspect something at the venue itself.


Things that might only interfere occasionally:

* mobile phone (registers with the network about once every 20 mins)
* smoke machine (Heating element on intermitently to maintain operating temp
* Air conditioning fans/motors at venue
* Are these the newer mackie 450's with a temp controlled fan?
* Dodgy Mobile Licensed bar with poorly maintained/unsuppressed pumps/coolers
* Some dastedly evil new noise limiter - controlling the DJ's desire for good audio, rather than the sockets...

thanks for the info. I think I will wait until this weekend is out of the way and then as like you said if it happens again then it may be the speaker.

No, these are the older versions, I got them as I knew there was problems with various parts on the new ones due to them being made somewhere else.

Hi just read posts with interest as ive had the same prob with mackies and other powered units ive used in the past, its almost defo another appliance on the same ring main circuit as you have used for the rig. For example i had loud clicking and buzzing coming from the speakers and it turned out to be the waitress's in the kitchen of the venue unplugging and plugging appliances in to wash up the buffet or cook food etc etc, the unplugging of appliances causes an earth spike in the cable (inductance) and the amps can be very sensitive to it (amplifying the sound) did the sound come from around the time they might of been using other power in the kitchen etc (ie buffet time) usually its a big appliance with a lot of inductance ie motorised equipment etc,........ central heating boilers are also renowned for causing interfearence on electrical lines as the stat switches on and off...have a bit of experience as im an electrician in the week!!!! So i hope ive helped a little

May well be an internal dry joint. Powered speakers, esp. the moulded RCF and Mackie can literally shake themselves apart over time. Later versions have hotmelt glue draped all over vunerable components.

I once had a JBL EON 15 with a similar problem and it was the mains switch occasionally arcing. Behringer Eurowaves have a similar fault whereby the legs of the output transistors suffer hairline fractures due to metal fatigue from all that vibration. The mackies shake power supply dropper resistors apart.

These faults can be Very Intermittent indeed.

K. Edwards