1 Reply Latest reply: Apr 25, 2012 8:12 AM by barme
barme Level 1 (0 points)

This is an information about problems related to USB, sound an Ethernet with a Thunderbolt displays (TD) connceted to a MacBook Pro.



  • MacBook Pro,
  • Thunderbolt display
  • Wifi and Ethernet connexion to the same network


Possible symptoms:

  • keybord (connected by USB) to the TD stops responding,
  • no sound and TD not visible in sound System Preferences,
  • no Ethernet connection through TD,
  • no battery charge by TD USB ports (iPad for example).


Soltions tried unsuccessfully:

  • smc or pram resets,
  • unplugging TD and/or MacBook Pro,
  • rebooting,
  • firmware and software updates,
  • multiple phone calls to Apple support,
  • TD mother board replacement,
  • TD power board replacement.


Solution that worked (found thanks to a clue given by Will.G on another thread in this forum):

  • deactivate Airport,
  • disconnect and reconnect the thunderbolt cable.


It looks like TD sound and USB ports are linked to the network Ethernet connexion...


Hope this will help those facing similar problems.

Thunderbolt display 27"
  • barme Level 1 (0 points)

    Unfortunately, it stopped functioning again.


    Maybe it is a cable problem ?


    One fact remains : Ethernet connexion, USB ports and sound work or don't work the three together