Guys with new iMacs, come in...

Are you using a firewire interface?? A lot of of hum problems on the mac forums were traced back to firewire interfaces, some said it was the fan noise being picked up

Edit: Nevermind, looks like a ground loop problem after reading the topic you posted
 
I've discovered that if I take my external hard drive out of the picture, there seems to be no noise. I have all of my samples and sessions on this disk. I never have any noise issues with my Macbook when this drive is plugged in. I am disappoint :(
 
Nah, it's still there.

Tried new cables n shit. My mate is on the lookout for something like the Hum X
 
i had this problem before,
it was a white imac with an alesis io26
i called alesis tech , they told me to plug everything into one outlet. ( meaning, computer, moniters, interface, anything else as well...)
have all of that plugged into a proper surge protector.
i know there is much better but this worked for me. monster 79.99 "power conditioner" at guitar center. works mint.
otherwise..... on amazon you can find whats called an isolation transformer.
that will solve all all your problems. enjoy!
 
Cheers man. I'm looking into my options. I've tried everything into one outlet and it made no odds. It could just be my house tbh
 
I've made a good few threads on the same problems. (admittedly not with apple gear). I got to it eventually, a combination of a couple of things. First thing to do is make sure all your main stuff is feeding off the same plug, make sure no power cables are crossing audio lines etc.

Intel speed step can also cause interference, unfortunately I don't think mac users can switch that off.
 
I'm going to try again. Thing is, I've got a fuckload of plugs. I reckon I need to see how many sockets I need and just buy a surge protector for that. When I put my new bass traps in, I'll actually be covering up a set of sockets anyway, so I'll have no choice but to fire everything off of one socket
 
Powering everything from the same socket seems to work most of the time, but as my post explained earlier, my flatmate had lots of noise if his monitor wasn't plugged to a different socket than the rest of the stuff.

But could be the electricity too. Years ago when I was still living with my parents, I remember that I used to have noise with my old pc from the lights being switched on and off in the house and the refrigerator's fans turning on. In this flat I'm living in now, it seems that the shitty small water boiler in our kitchen causes some slight chirping style noise in my monitors when it's on, go figure.
 
May be a silly question, but are you using balanced cables for your monitors? If you're using instrument cables they're much more prone to RF interference for lo-z signals.

I had this problem with a Seagate drive a long time ago, it got into anything that was an unbalanced cable. I have no such problems with my new iMac though, check out the Monster floor strips, they have some power filtering on them and they're not too expensive. You'd be surprised what dirty power can do.

edit: not sure if Monster makes anything for Euro standards
 
Also having this problem with a newer iMac. From everything I've read the interference is caused by a faulty dimmer circuit inside the computer...the noise will become more apparent as the circuit gets closer to dying completely.

Such bullshit.
 
Well, did some more fucking around tonight. When I change the buffer size/host processors/cpu usage limit, the noise alters. It also lessens with load on the CPU. So, the less plug-ins I use, the less noise I get. What a bitch!
 
Finally fixed this.

Snipped pin 1 on the XLR end of my monitor cables. Noise gone.

Cheers for all the tips guys :)
 
Still blaming my iMac, but everything is still safe because the speakers are grounded by the plug. It's annoying, but I'm not getting noise now