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theromanone

macrumors member
Original poster
Dec 29, 2011
32
0
Pretty much after having my mini display port to hdmi hooked up and trying to get the resolution of my tv (720p) to show the whole screen without being cut off (annoying in itself) found this:

Buzzing whenever I have my speakers plugged into my headphone jack and I then also plug in the mini display port to hdmi. Changing the volume of the OS does not change the volume of the buzzing whatsoever. I can put the jack back in and take the mini port cord out, and the buzzing stops. Put the mini port back in, and buzzing commences.

What could be the problem? This is a 18 hour old macbook pro, brand new shipped earlier yesterday.
 
I don't think it's your mac. You have what is known as an earth hum.....This can be a devil to trace, as it's to do with the electricity sockets in your home...A couple of things you can try.

Try unplugging the equipment and use a different socket. You can buy earth hum eliminators from a few places:


http://www.amazon.co.uk/s/?ie=UTF8&...=aps&hvadid=5797078976&ref=pd_sl_6mizbwhvxm_b

I'm pretty sure this would solve your issue.
 
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this also just happened with just the mini display port to hdmi cord plugged in and nothing in the headphone/mic jacks. This time, however, the sound buzzing volume was able to be controlled by manipulating the TV volume (which was from there the sound was coming from).

I've never, never had anything like this in the 3 years I've been doing headphone and hdmi outs at the same time with my crappy HP. Really the earth hum? I did notice I have more static electricity using this laptop, didn't think I'd have to worry about having to get an adapter for my house because the mbp can't properly handle a simple audio and video output?

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sounds like this but with less "radio static":
http://www.youtube.com/watch?v=Wm3fUDq7aos
 
That's an earth issue for sure....That buzz doesn't really disappear at low volume, it's just reduced. If you can to be sure it's not your mac, try it at a friends? I'm still betting on the earth hum though.
 
weird.. you may be right, get this:

changed my power outlet brick in the same room that's plugged into the lower of the two plugs in the outlet, the same one that's standard everywhere with two three prongs, (into this brick goes my spare laptop, lamp, and external hard drive all plugged into this brick/secondary plug.) The second (upper) plug of the same wall outlet is for my current mbp. My speakers that are plugged into the headphone jack in the mbp are plugged into another power outlet brick going to a completely different outlet on the next wall of the same room.

The kicker: moving the lamp plug in and out from the first power outlet brick makes static come out from the speakers!

Also, I should mention that earlier today I did have 3-4 instances where randomly there would be a static "pop" from the macbook pro to the speakers.

The house is definitely not new, on the 3rd floor.

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Also, I live in the states, all the products listen on your amazon were for European-style plug outlets.. does this hum only happen over there, and maybe it's not applicable to our wattage/outlet system?
 
That's about the right money....More expensive here. I guess they take the same approach....It's cheaper than re-wiring your house. Ive used them in recording situations in non studio situations....They work well.
 
You have what is known as a ground loop. It occurs when you have several conflicting points of ground (such as someone took a short cut and grounded an outlet to a pipe within the house instead of correctly wiring back to the main ground). The fix can be a horrendous search as others have said and sometimes it can be as simple as the replacement of an outlet.

I would try the different connectors included with the MBP power adapter first. Sometimes the quickest and easiest fix is to use what is called a cheater plug, which takes the 3 prong of the plug and changes to a 2 prong to go into the outlet (some have been known to cut the third lead, the ground lead, off of the plug itself although it is not the safest or recommended way). Since the MBP comes with a 2 prong adaptor i would try it first and see if things get better.

Lots of high end electronics avoid the three prong (grounded adaptors) to alleviate the chance of a ground loop. If you need one, search for a ground loop isolator. Really good ones cost lots, but they work well, in your situation, I would recommend a good UPS with separation as a really good UPS/ surge protector combination unit as it will alleviate ground loops as well due to the nature of the design and add protection.
 
thanks guys, won't be able to afford anything for a week or so, I'm already only using the two prong as of now for the charger, haven't even unrolled the three prong as of yet.

Maybe use an extension cord from another room? Decisions decisions.
 
I would try the 3 prong if I were you as maybe your MBP is building a charge from "dirty" power and the 3 prong may help to alleviate the ground problem (some here have reported static build up when not using the 3 prong grounded plug and the issues being resolved with the 3 prong plug. It may be all you need and save you an added cost. Heck you already have it so why not give it a try.
 
For some reason, now it seems my right speaker has been shorted (they're the M-Audio BX5a's, a few hundred bucks and only 3 months old). It's volume is maybe a quarter of that on the right side and sounds tinny, i.e.: just treble and no lower end/bass whatsoever.

Maybe I have too many things plugged into the same socket? Again trying to do different things until I can afford the earth hum bypass.

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I would try the 3 prong if I were you as maybe your MBP is building a charge from "dirty" power and the 3 prong may help to alleviate the ground problem (some here have reported static build up when not using the 3 prong grounded plug and the issues being resolved with the 3 prong plug. It may be all you need and save you an added cost. Heck you already have it so why not give it a try.

Just did this, and SPEAKER FIXED! Makes sense with the static, since I definitely felt a "shock" after using the laptop for the first time for an hour, plugged in via the 2-prong, when touching the sink in the kitchen.

Never would have thought of that fix, ever, thanks a lot!
 
I don't think it's your mac. You have what is known as an earth hum.....This can be a devil to trace, as it's to do with the electricity sockets in your home...A couple of things you can try.

Try unplugging the equipment and use a different socket. You can buy earth hum eliminators from a few places:


http://www.amazon.co.uk/s/?ie=UTF8&...=aps&hvadid=5797078976&ref=pd_sl_6mizbwhvxm_b

I'm pretty sure this would solve your issue.

I know this is an old thread, but just needed to say thank you Macman45 for that. Hade the same issue as the OP, and found that unplugging the charger for my MBP eliminated the noise and replugging it made it come back instantly. I unplugged the dimmer lamp from the extension lead and that seems to have removed it. Now I finally know what's causing the issue! :D :)
 
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Just to add to this. I also have crackle and buzz in my headphones on my Mac Pro 5,1.

If I plug the headphones in directly (I tried two different pairs of headphones) the crackle disappears. I tried this in the headphone port on the front and the line out on the back.

My issue is a headphone extension cable.

It's the type that allows you to answer a call with in ear headphones on your Mac and has three rings on the sleeve of the jack.
 
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