No brightness or sound on Thunderbolt display

[athens622]

I plugged my Apple Thunderbolt display in to my 2011 Macbook Pro via thunderbolt port and power supply.
The Macbook recognizes the monitor as a second display, but I have no brightness controls or sound output on the Thunderbolt display.

I have tried:
- restarting the Macbook
- disconnecting the display
- Unplugging the main power supply
- starting up in safe mode

None of the above worked.

 

[athens622]

These two images show that there is no brightness slider in the Thunderbolt's display preferences, and there is no Thunderbolt device in sound outputs.

 

[colshine]

Try reseting the NVRAM:

http://support.apple.com/kb/HT1379

 

[athens622]

I just reset my NVRAM, still nothing..

 

[Skip Paris]

Usb

i just reset my nvram, still nothing..

 

[athens622]

I may be wrong, but the USB solution is for Cinema Displays. The Thunderbolt display does not have a USB out cable. It only has a Thunderbolt cable and an external power cable.

Do you mean that I should plug a seperate USB cable in to one of the ports on the back of the monitor?

This may fry the monitor..

 

[colshine]

Sounds like the display is faulty. Have you contacted Apple?