Audacity Forum

All of my microphone setup and everything is working fine.
The problem lies within my computer, and idk what's going on.
Here's my microphone recording plain silence, and as you can see the input line (blue one) is way higher then it should be.
It's SUPPOSED to be in the middle, with the black line. But even if I don't have a microphone attached to my computer and hit record,
the blue line STILL stays above the black line.
Here's what it looks like:



You see how the blue line is above the black line?
I don't know why it's doing that. I even have my microphone boost turned all the way off.
When I lower the input level, the blue line goes down, BUT...
The two lines only match up (like they should) when the input level hits 0. And that's when I'm not recording anything.
I don't know what to do, because when I record, all of the top half of the audio wave gets cut off.
The blue line and the black line are BOTH supposed to be in the middle.
Like I said, my microphone/mixer aren't the problem, I've checked.
This hasn't ever happened before, and I'm not sure what I did.
I've already tried fixing all the control panel>Sound options, and it's something else.
Please, does anybody know how to fix this?

(Oh, by the way, I know this picture is of Audacity 1.3 beta, but this problem is occurring with both versions, so I know it's a problem with my system.)

You have what is know as DC-offset - normally a fault with your soundcard - and yours looks a fairly extreme case.

You can correct for it after recording by using the Normalize effect. Do the DC-offset correction immediately after capture - but =do not at that stage apply any normalization.

WC

definitely the sound card
one channel looks dead
the other one has a huge dc offset problem

i would consider an outboard audio interface card
if after fixing the dc offset via normalise
any other problems are still visible

When I normalize it, it DOES fix the DC, HOWEVER...
The problem still resides. When I hit record, it records everything way too high.
Is there no way to apply a constant DC offset? There is no other problem when recording, both left and right channels work fine.
However, the DC causes the wave to clip at the top, and not be long enough at the bottom.

No - it is your vsoundcard that is applying the DC offset - you need to fix that Probably by replacing the soundcard or using an external USB soundcard). Or put up with the workaround as Audacity does no processing in realtime while recording (though this is an oft requested feature request).

WC