Really annoying audio interference issue

[Fire Lancer]

This keeps coming up with different devices and is really annoying.

Firstly there was my as of yet unresolved issue with USB audio ( http/www.tomshardware.com/forum/56730-6-audio-interference ) and now I have run into an issue when connecting the line out of one device (laptop) with the line in one my desktop Although this time I was thus able to record exactly what it is...

edited to remove suspect audio link -- Moderator

But connecting my desktops line out to it's own line in (with the same cable) yields no interference

My laptops and desktops audio out has no interference issues when connected to speakers, headphones, etc (with the exception of the usb varieties...) ....


Laptop -> USB audio - interference
Desktop -> USB audio - interference
Laptop -> Speakers - fine
Desktop -> Speakers - fine
Laptop -> Desktop line in - interference
Desktop -> Desktop line in - fine


So I am really out of ideas here, since each component excluding the previous USB audio problem seems to work fine some cases...

 

[soundguruman]

i havent listened to the audio you recorded.. and after what was said about the website, i am not going to either.
a ground problem generally does cause a constant hum.


Oh yes it can. When grounds from two places connect to the same device, it will hum like a bee.
The two places being cable TV and the three prong power plug ground at the same time.

OR DSL ground, and another devices ground at the same time



if your hum isnt constant, i have no idea.

Disconnect the cable TV or internet from cable, or DSL, does the hum go away?

Using a three prong to two prong power adapter, disconnect the power ground, does the hum go away?

Disconnect the power ground from the computer monitor, with the adapter does the hum go away?

 

[fitrihadidotcom]

I also have the same problem with my speaker when the speaker's usb connect to the PC. Simple solution. Just buy a USB socket plug and use it for the USB speaker. The electric noise is gone forever.