Input Sound Buzz

hello all,
i’ve got a problem with the sound coming from the input source: i get a loud buzz through it. i’ve tried different sound cards (onboard, turtle beach reviera), different cables, different input sources. i get the same buzz with every combination. anything that i should look at that i haven’t thought of yet?

muchos gracias

Need more info. Is this a dual-boot machine, and if so, do you get the buzz under Windows? If you’re using Pulse Audio, have you tried an alternative such as ALSA?

(Personal opinion: Pulse might be a wonderful thing some day, but at present, it ain’t ready for prime time. At all.)

Does the buzz remain even when you completely disconnect everything from the input jacks on the card?

This could be a hardware issue, possibly one to do with grounding, or with a bad power supply. You haven’t by some chance cut the ground pin off of your AC plug, have you? :slight_smile:

You should also check the routing of the cables (if any) inside the computer’s case.

Finally, make sure it’s not simply a level issue. If the input is set for microphone (meaning, “very high gain”) and you plug a high-level source into it, you’re going to get terrible hum and noise.

Provide more details.

have you thought of turning down the input source in your mixer…or
(i use KMix, you didn’t say what you use) in the “Switches” tab try
turning off “Mic Boost (+20dB)”

that is, if your noisy input source is a microphone (you didn’t
mention what kind of input source you are using, or how it is
connected, mechanically…i mean, if it is an old 8-Track connected
via battery cables is it probably gonna be noisy)… :wink:

maybe it is just a matter of providing a common ground to both the
computer and the input device…mismatched ground often allows line
power to introduce a 50/60 hz hum…


platinum

sorry for leaving out those details. the audio is the base setup, so pulseaudio. i don’t get a buzz when there’s nothing plugged into the input jack. the input source is either a tv or cable box. it’s suse 11.1 only, so i don’t know what it’d do under windows.
i had this setup working a couple of months ago, before i moved. the only thing that i can think that’s changed is software updates. i’ll try un-installing pulseaudio and see what that does.
oh, and as to the mixer settings, i’ve got to turn them up to around 90% to be able to hear it decently.

> i had this setup working a couple of months ago, before i moved.

ok…maybe it is a grounding problem…

is your TV and cable box plugged into main power nearby?

TRY this: with the TV off, remove the power cord from main power, flip
it so that you plug it in the other way (left prong now inserted into
the right socket–HEY, i have NO idea where in the world you are, and
maybe all your plugs have THREE prongs, so this wont work for you)…

then, turn on TV and see if the hum is gone, or less…

also, sometimes running speaker wires along side power cords can allow
some leakage into the sound system, causing a hum…

instead of running power and sound cords parallel to each other for
long (a relative term) runs, separate them and see if that helps…


platinum

thanks for all of the help. it turned out to be caused by the cable box. i had to take the input from the tv and move my pc away from the cable box another foot or so. weird.

it36582 wrote:
> thanks for all of the help. it turned out to be caused by the cable
> box. i had to take the input from the tv and move my pc away from the
> cable box another foot or so. weird.

same kinda thing i was talking about…could be cable box ‘leaking’
radio frequency and the sound system wires (or something inside your
PC) acting as an antenna and then feeding the ‘noise’ through the
input to the sound amp…


platinum

On Sun, 20 Sep 2009 11:15:03 GMT, platinum
<platinum@no-mx.forums.opensuse.org> wrote:

>it36582 wrote:
>> thanks for all of the help. it turned out to be caused by the cable
>> box. i had to take the input from the tv and move my pc away from the
>> cable box another foot or so. weird.
>
>same kinda thing i was talking about…could be cable box ‘leaking’
>radio frequency and the sound system wires (or something inside your
>PC) acting as an antenna and then feeding the ‘noise’ through the
>input to the sound amp…

If OP has a CRT type TV it may have been distance from the TV that
remedied the problem.