Hear a buzzing sound when connecting laptop to TV? This is how to fix it

This has been getting a lot of hits, so clearly, it’s a common problem! If this advice helps you, or does not help you, I’d appreciate it if you could leave a comment so I can see if the instructions need to be clearer (ie, more pictures and whatnot).

This is 100% unrelated to anything else on this blog, but I am submitting it on the off chance that my recent experience can help someone else out there. Like a public service announcement! I did a few Google searches to help me solve this problem and the web was full of bad advice, although eventually I did find the right solution, which I present below.

The setup:
Connected laptop to TV via RGB cable and simple audio cable. Video came in fine. Audio was mostly fine, except for one problem….

The problem: When laptop was plugged into electricity, the TV speakers made a very annoying buzzing noise. When running off battery, no such noise. Laptop is old, and battery lasts less than an hour, requiring it to be plugged in. What an odd problem to have!

The good news is that there is an easy solution.

Technical name for problem: Electrical interference caused by loop in grounding wires. Basically, when the laptop was plugged in, and the TV/speakers were plugged in, they managed to interfere with each other in some magic electrical way.

Solution: 50 cent three prong to two prong adapter.

Purchased this little thing at the hardware store. 2 for 99 cents.

Photobucket

Three prongs go in one side, two prongs come out the other.

Simply plugged laptop into adapter and then adapter into wall.

Buzzing noise has been vanished forever. Hooray!

So if you have this problem, try this very simple solution!

Further advice if the problem persists:
Note that the adapter has a little metal loop which tries to make contact with a screw in the outlet and act as a grounding device. This will obviously cause the problem to return. Either bend that piece of metal back or remove if it makes contact and the problem returns.

If the problem still exists, try using a second adapter on the TV or speaker system as well to avoid grounding those and encountering interference.

18 Replies to “Hear a buzzing sound when connecting laptop to TV? This is how to fix it”

  1. Did not work. still getting a buzzing noise whether i hook the adapter to the laptop, and in the wall or the tv and in the wall

    1. Just to confirm, youre using two adapters, one on the laptop, one on the TV? Did you make sure that metal piece was pulled back so it doesnt touch the screw on the wall panel?

  2. This is amazing. The first plug we placed on the end of the TV plug and 90% of the buzz was gone. We then put another on the PC power cord and the buzz disappeared entirely.

      1. https://web.mit.edu/jhawk/tmp/p/EST016_Ground_Loops_handout.pdf
        Consider two devices connected by a signal cable, each device having a 3-prong ac plug. One device has a ground “lifter” on its ac plug and the other doesn’t. If a fault occurs in the “lifted” device, the fault current flows through the signal cable to get to the grounded device. It’s very likely that the cable will melt and burn! Defeating safety grounding is both dangerous and illegal – it also makes you legally liable!

        CEDIA EST016 UNDERSTANDING, FINDING, & ELIMINATING GROUND LOOPS Page 7
        In a typical year, consumer audio and video equipment electrocutes 10 people and causes some 2,000 residential fires which result in 100 civilian injuries, 20 deaths, and over $30 million in property losses. [6] [7]
        [6] Hiser, S., 1997 Electrocutions Associated with the Use of Consumer Products, United States Consumer Products
        Safety Commission, 2000, http://www.cpsc.gov
        [7] Mah, J. et al, 1997 Residential Fire Loss Estimates, United States Consumer Products Safety Commission, 2000,
        http://www.cpsc.gov

      2. https://en.wikipedia.org/wiki/Cheater_plug#Safety
        In the professional audio and video fields, the cheater plug has been identified as a serious safety problem. Its casual use as a method for avoiding ground loops in analog audio and video signals (to eliminate hums and buzzes) is dangerous.[5] Bill Whitlock, president of Jensen Transformers, writes, “never, ever use devices such as 3 to 2-prong AC plug adapters, a.k.a. ‘ground lifters’, to solve a noise problem!”[5] Whitlock relates how an electrical fault in one device that is connected to its electricity source through an ungrounded cheater plug will result in dangerous, high current flowing through audio or video cables. Whitlock notes that in 1997, consumer audio and video equipment electrocuted nine people.[5]

        1. Brandon, this post was really intended for people at home, not professionals. And frankly, it’s really not relevant any more.

          ” laptop to TV via RGB cable”

          Thats very 2011! Today the streaming programs are built into the TV, or people use Chrome Cast or Apple Air.

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