Intermittent vibration on Macbook Air when connected to power supply

I have this problem too. Mine is a 2016 Macbook Pro 15"model.

It's definitely either a grounding problem and a current leakage problem. If i touch the MBP with my leg on the floor barefoot, i will feel the tingle. And then i climbed onto a plastic chair ( an insulator ), the tingle disappeared instantly.

So a solution is to wear a thick enough rubber shoe? Or place a rubber mat below your desk so that you can rest your feet on!!

This was happening to me just now.

Very strange:

1. Experienced the "vibration" issue.

2. Unplugged the MBP, it stopped.

3. Plugged in the MBP, it started again.

4. Unplugged again, stopped.

5. Plugged in again, no issue. huh?

6. Plugged and unplugged several times. No issue. Weird.

Battery is at 100%. Could that have something to do with it?

Waited until batter was 50% and rechecked. Nothing. No issue. Bizarre.

Current in my home is normal. New-ish home. Checked line condition. Perfect.

Can't explain it.

I have exactly the same issue - except for me it is far more consistent. Every time my MacBook Air (late 2010 model) is on mains charge, it gives me the shock / vibration. I have also noticed that my charger itself seems to be giving some flow of eletricity on the outer cylindrical casing of the power connector - contacted at the right point I most definitely get a shock. I've just contacted Apple to seek a replacement power supply - I think this will do the trick. You're well within warranty, so if you haven't already, I'd recommend the same. Apple should be well aware of this common issue by now. Good luck!

Brian is correct. The power adapter places one-half of the line voltage, at a very low current - it's well within the international safety standards - onto the computer chassis and, therefore, the metal case. If you use the 3 prong AC input cable, plugged into a properly grounded outlet, the problem will be alleviated.

You'll notice the same situation if the MBA is running a battery, and you plug an ungrounded accessory (a printer, for example) into the USB outlet.

The situation is well-known by Apple, and represents normal operation. The current leakage allows an ungrounded computer to meet international radiation emissions standards.

I too have to same problem. I actually went into the apple shop and was told it was the hard drive which i found quite amusing, I'm no computer expert but im pretty sure that the hard drive should be functioning both with and without the power cord??

I use the 3 pronged plug and still have this problem. I say 'problem' but its not really a shock so it doesnt bother me that much and too be honest the battery life is amazing so i never really need to plug it in except when it is off to charge it.

ive also plugged it into every socket imaginable including in university. I also had a cheeky little rub of a macbook air in the apple shop and they were doing the same thing so I am assuming that it is normal??

I haven't noticed this on my 11" MBA, so I'm speculating.

Could it be that recharging the battery generates enough heat to cause the fan to start up?

I dont think so, it's not like an ongoing constant vibration its like a charge when you touch it. It's hard to explain, if it is the same thing that i have, if you lightly run your finger along the case it vibrates back but it doesnt vibrate on its own....its bizarre.

@beccaxbutterfly - aptly described - that is spot on the same problem I have.

I would agree with other comments that it isn't 'dangerous', but it is quite annoying. I am a UK user, where a 3 pin plug is the only option. I have tried it any many sites where the electrics are very good (and no doubt grounded properly) and the issue is constantly there. I did try seeing whether the Airs in the Apple store had the same problem, running my finger across 5 different units. It wasn't a problem - although this could well be because I was a) wearing shoes with an insulated sole or b) that the security cable was also acting inadvertently as a ground (I can't recall what they're made of).

I live a few hundred metres from an official Apple repair shop, so will be popping down there with my Air next week, and seeing what they make of it all.

Will let you guys know the outcome! 🙂

wana have even stranger thig:

touching my apple air with one hand then touching anybody with my other hand would give the same sensation of vibration.

i just purchased my MacBook Air 13" 256 GB SSD 2011 today in Kuala Lumpur, Malaysia, and i too noticed this so called "vibration/electrostatic sensation" problem when the mains is plugged into the wall socket.

initially, i thought it was a normal feature of Mac's, as this would be my first MacBook i'm owning. however, i thought about my friends MacBooks and they don't have this problem, and all the display demos in the Apple outlets. the feeling is described as vibrations or ever slight eletrostatic discharges when i place either or both hands on the metallic unibody. and i wasn't comfortable with such a feedback. what was worse was, i thought about leaving it charge for awhile without touching it, and when i handled my MBA, i got a severe shock!

i Googled and found many people have this issue. and it has persisted in different countries around the world since 2007. i found it appaling that such an expensive piece of hardware could have a potentially health hazard and/or poor quality control.

many websites/posters blamed it on the a faulty MB or 45W MagSafe Power Adapter, or poor grounding of the outlet/building power supply, which i thought was ridiculous as i've not had any electrical problems with all my other electrical appliances.

i followed different advice, including getting a voltage regulator, moving to different power sockets, or even charging from different building/sites, however, the problem still was there. i even used the grounded 3-pronged head provided instead of the default 2-prong head (in Malaysia, we use the same 3-hole socket types like in the UK/Ireland), but felt that there was a current leakage into my MBA unibody.

SOLVED: until, i found a post by someone who suggested using the AC extension power cord also provided in addition to the MagSage Power Adapter. and it worked! no more vibration or "electrostatic discharge" on the unibody.

and then i wondered, why in the world should there be a difference. i thought perhaps, the MagSage Power Adapter was faulted. and then i looked closer at the Wattage and Current ratings.... what a shock!

OBSERVATIONS: i found there were slight different fuse ratings used in all 4 components MagSafe Power Adapter, default 2-prong adapter head, 3-prong adapter head and the AC extension power cord.

MagSafe Power Adapter body: Output 14.5V 3.1A (Voltage/Current supplied to MBA)

2-prong adapter head: Input 125V~ 2.5A (Voltage used in countries like the USA)

3-prong adapter head: Input 100-240V 2.5A (for countries that use 220V like the UK, and for additional grounding for all countries)

AC extension power cord: Input 100-250V 3A (notice the higher fuse rating)

i may be wrong, but the 0.5-06A difference of current from the input to output, may be allowed to leaked into the MBA, and cause vibrations/electrostatic discharges when touched, and i think may damage the components down the road.

the only to see if my theory is correct is to go to the hardware store and obtain a 3.0A fuse and replace that in the 3-prong adapter head and see if it resolves the problem. i will let you guys know.

but in the meantime for people who have that problem, i recommend using the AC extension power cord as well.

good luck!

sweejin - I applaud you sir for having the decency to share this info - thank you 😀

I have just tried exactly your suggestion with the cable / adapter switch, and can confirm the irritating 'vibration' effect has gone! Switch back to the non-extension, and the problem returns.

I will be very interested to hear how you get on with the fuse test. I don't quite follow the logic (forgive me, that might just be my ignorance) as if the MagSafe Power body with its 3.1 Amp fuse was connected to the adapter head with a 2.5A fuse, if it actually pulled a current higher than 2.5, wouldn't this cause the fuse to break in the plug? Or perhaps your thinking is it terminating the 'spare' current in the body of the Mac somehow, instead of breaking the fuse (which with magnets next to power inputs, perhaps is possible - I have a limited knowledge of electricty, but somehow a magnetic field next to a power input troubles me).

But in short, thanks so much, and I will be grateful to hear how you get on with the fuse change 😀

Many thanks indeed