Cannot hear Line-In through USB headphone

[Guest]

OK Audiophiles, here is something that has been bugging me for quite some time.

I cannot hear the Line-In audio through my USB headset. However, I CAN hear
it through my desktop speakers. All other sounds CAN be heard through the
headset.

I've tried changing the default device to the USB headset in Sounds and
Audio Device Properties, but it makes no difference for Line-In.

I thought it might be the software for my Plantronics headset, so I bought a
Logitech USB 350, which has no software or drivers. However, I still cannot
hear the Line-In audio through the headset. Nothing is muted in the volume
controls and as I stated above, I CAN hear the Line-In audio through the
desktop speakers.

In the Nvidia Mixer program, I can see the spectrum graph moving when the
line-in is playing. The "Digitize Input" option for Line-In does not make
any difference.

I also tried installing a Creative Labs Sound Blaster Live card and used
that Line-In port, but it had the same problem.

Any ideas?

 

[Guest]

Line-in is an Option feature of your soundcard and has nothing to do
with your USB headphones for they have their own built-in sound producing
features. Suggest you contact the Logitech website for tech support
or Google search for information.