8 Replies Latest reply: Sep 15, 2015 2:53 PM by aramis from italy
Bonferroni Level 1 (0 points)

My Thunderbolt display has developed a problem in which a sound comes from the left side when the monitor is at a brightness level greater than 40%.  The sound is like that of a fly's wings stuck in something but it only occurs when the following are present:  1) monitor plugged in, 2) monitor connected to laptop, 3) the brightness is greater than 40% of the total amount in settings.


Has anyone had this problem and if so, what was the fix?

Thunderbolt Display (27-inch), Mac OS X (10.7.5)
  • Bonferroni Level 1 (0 points)

    I can also set the brightness higher than 40% if the screen is dark.  For instance, my background is black.  When the background is showing and brightness is 60% there is no noise.  When I display a webpage in Firefox (like the Apple forum), the noise comes back.

  • Verre Tigre Level 1 (0 points)

    Mine started to have this very annoying noise right after one year warranty. I have to bring it in for service twice. The first time the technician could not identify the problem and changed the display motherboard and charged us HK$1700+. The noise existed after the "service". The second time we brought it in, the technician could not find the problem and changed the sepakers and charged us HK$300+. Now the noise is till there, I am not sure what the technician is going to change this time, the stand or the case, maybe? The only thing that I am sure that they will not change is the whole montor. Apple's service ***** really badly. If they are not going to fix the problem, I may have to bring it in an Apple and smash the monitor right there on the flloor!!! I am still not sure even after that will I feel a little bit better about this stupid service looping game that Apple sets up!!!

  • XeonMF Level 1 (0 points)

    Mine too. A large noise like current noise.

    And the noise goes done as the screen dimmer

  • GeorgHoller Level 1 (0 points)

    I have same Problem, since some days after warrenty.

  • givealoha Level 1 (0 points)

    EXACT same issue. Help?!?!

  • pcevandijk Level 1 (0 points)

    I also had this problem. Tried everything, nothing helped.


    Today i replaced the power unit of my 27 inch Thunderbolt display. Problem solved.

    So it seems to be a hardware problem.

  • sludesign Level 1 (0 points)

    Unplugging the connector on the back of the Thunderbolt Display and replugging it in fixed the problem for me.

  • aramis from italy Level 1 (0 points)

    Avevo lo stesso problema con il mio monitor apple 27" che improvvisamente dopo un paio di anni dall'acquisto ha iniziato a ronzare/friggere.

    Il rumore era direttamente proporzionale alla intensità di illuminazione.

    La causa è da attribuire alla spirale contenuta nell'EMI filtro del monitor che è priva di lacca di protezione anti vibrazione risonanza.

    Ho risolto in questo modo: aperto il monitor, ho tolto la scheda power, e smontato l'altoparlante centrale, fino a raggiungere l'EMI Filtro, posto internamente in corrispondenza con l'ingresso del cavo di alimentazione. Questo Emi Filtro è una scatolina metallica che ho smontato dallo chassis ed ho aperto (a fatica con l'utilizzo di un saldatore stagno per rimuovere punti di fissaggio.

    All'interno è ben visibile una spirale di rame, la quale nel mio caso era priva della lacca di protezione antirisonanza.

    Ho preso del banale smalto per unghie trasparente ed ho inondato la spirale fino a ricoprirla il più possibile. La stessa cosa per sicurezza ho fatto anche con le spirali che sono visibili sulla scheda power.

    Rimontato il tutto il ronzio è sparito definitivamente.

    Problema risolto con 1 euro di smalto e 1 o 2 ore di lavoro.


    I had the same problem with my monitor apple 27 " that suddenly after a few years of purchase started to hum/buzz/fry.

    The noise was directly proportional to the intensity of illumination.

    The cause of this problem is due to spiral contained into the hemi filter monitor that lacks lacquer anti vibration resonance.

    I solved this way: open the monitor, I removed the card power, and removed the center speaker, until you reach the EMI filter, place internally at the input of the power cord. This EMI filter is a metal box which I disassembled from the chassis and opened (with difficulty with the use of a soldering tin to remove the fixing points.

    Inside it is clearly visible a copper IUD, which in my case was devoid of protective lacquer anti-resonance.

    I took the ordinary nail polish transparent and have flooded the spiral up to cover it as much as possible. The same thing I've done for safety even with spirals that are visible on the power card.

    Reassembled all the buzz is gone for good.

    Problem solved with 1 € of enamel and 1 or 2 hours of work