Probable Causes:
1) The headset may be installed and running under Windows 98 (First Edition).
2) You could have exceeded the allocated power on your USB port, rendering the mute switch inactive.
3) Possible Human Interface Device conflict or missing drivers.
Solution(s):
1) This mute feature is not supported under Windows 98 (First Edition).
Upgrade to Windows 98 Second Edition or a higher version of Windows to allow the mute switch to work correctly.
2) Disconnect the headset, and then reconnect it to see if this reactivates the mute switch. If so, then you might have insufficient USB power.
3) You could be missing a driver.
Go to "Device Manager" (instructions below) and look for Human Interface Device. Make sure there are no conflicts on the HID Compliant Consumer Control Device or the USB Human Interface Device.
If you have other USB devices, these drivers could be listed more than once. If there are any conflicts, make sure that they are in reference to your DSP headset, and then attempt to update those drivers. You might need to reinsert your operating system CD so that the headset can find these drivers. Detailed instructions are listed below.
Drivers (NO Drivers are needed for a MAC computer)
There are five drivers needed to run the DSP headsets. Four of these drivers are from the Windows operating systems and one is from the PerSono software if the customer has it installed in their computer.
These drivers are located in the Device Manager.
To get to the Device Manager:
For Windows 98 SE and Windows ME:
1) Click on Start then Settings then Control Panel.
2) In the Control Panel, click on System.
3) In the System Properties window click on the Device Manager tab.
For Windows 2000:
1) Click on Start then Settings then Control Panel.
2) In the Control Panel, click on System.
2) In the System Properties window click on the Hardware tab and then click on the Device Manager button.
For Windows XP & Vista:
1) Click on Start then Control Panel.
2) In the Control Panel click, on System.
3) In the System Properties window click on the Hardware tab and then click on the Device Manager button.
The Windows drivers in the Device Manager are as follows, the bolded headings are listed in alphabetical order:
Human Interface Devices: (Click on the + sign to the lift of it to show:)
HID Compliant Consumer Control Device
USB Human Interface Device
Sound Video and Game Controllers: (Click on the + sign to the lift of it:)
USB Audio Device
Universal Serial Bus controllers: (Click on the + sign to the lift of it to show:)
USB Composite device
Plantronics USB Bulk Driver or Plantronics USB Audio Adapter.


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Once again thank you for the prompt and professional service
