Dave, I don't know your headset but if it is skype compatible that 
button may answer a call.

Don


On 7/17/2015 9:04 AM, David Pearson wrote:
> Hello List:
>
> I have a Logitech headset(possibly model #390), but not positive.  It's
> plugged into an available USB port located on the front of the pc tower, and
> seems to be functioning.
>
> There is a plastic block along the headset wire(one side of which is
> smooth).  On the other side of this block there seems to be a smooth button
> surrounded by a plastic ring.  Pushing on this plastic ring seems to
> raise/lower the headset volume level(depending on which side of
> ring(top/bottom) is pushed, but I can't figure out what the smooth feelling
> button in the center of this volume ring is for.  No documentation came with
> this headset, and I'd appreaciate it if someone could "enlighten" me as to
> its purpose.
>
> Sincerely yours,
>
>
>
> David S. Pearson-wa4dsp
>
>
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