Volume bar on T23 missing

[likesspace]

Hi guys,
I used to have a green volume bar that showed up on my LCD when either increasing or decreasing the volume (via the keyboard).
All of a sudden this volume bar has gone missing and in fact never has shown up on two of my other T23 computers.
Also, I recently purchased 2 T43 computers and the volume bar does not show up on either of them. The volume itself DOES increase, but I just don't get the graphical display on the LCD.
If anyone has any ideas on what is causing this I'd really like to hear your ideas. All of the FN combination keys do work so I feel as if my hotkeys are up to date.
Thanks in adavance.

Dave

[likesspace]

Never mind.....
I downloaded the latest drivers and all is well on all computers. I had MOST of the hotkey drivers installed but not all of them. Still not sure why it disappeared on one of the machines but it's working now.
Thanks anyway.

Dave