Hello!
I recently updated audacity to 3.7.3 since then I have a continuous white noise on the left channel as soon as I start the recording. My first thought was my micro (Rode NT USB) is broken or the cable. Both is replaced by a new product - the noise remains. I tried it on different windows computers, also in work - the noise remains. I tried different micros - the noise remains. The company which checked my micro uses audacity 3.7.0 - the noise does not appear.
So the only possible conclusion is: there is a bug with audacity 3.7.3 introduced - are there any similar experiences? Where can I submit bugs?
I uploaded a screen shot so that you can see what I mean.
Also, make sure Windows “enhancements” are turned OFF. They can cause all kinds of weird problems and there’s a slight chance that there is automatic gain control turning-up the volume when there is little or no sound.
There is always SOME noise from analog electronics and since preamps have lots of gain, the noise gets amplified.
Rode has a good reputation but perhaps your mic is defective.
And of course there is acoustic noise in the room. In a “soundproof studio” the acoustic noise is often worse than any electronic noise.
If it’s a high-pitch “whine” it’s probably noise from the USB power getting into the preamp. USB power is notoriously noisy (not a problem for digital). Some computers are worse than others and some USB mics or USB-powered interfaces are better filtered than others so it can vary a lot.
You can try a powered USB hub, or there are USB isolators, but if you get one make sure the power is isolated (which means the power is “re-generated” and there is no “direct” power or ground connection between the computer and USB device).
Dear DVDdoug,
thank you very much for your answer and hints.
I can definitely prove that the noise is caused by Audacity, due to the following facts (see also my original posting):
I installed an older version of audacity now - 3.7.0 - and there is no noise on the left channel (see the uploaded screenshot of my original posting to understand what I mean).
I install audacity 3.7.3 - and there is a noise on the left channel
I tried it with two different microphones on 4 different PCs - always with audacity 3.7.3 - the noise is there
I replaced my RODE micro with a completely new one - the noise is still there
So sorry, but when looking at the facts above it can in my eyes only be the SW audacity itself, and there the version 3.7.3 - which causes this noise. Also it cannot be any windows enhancements - because when I use audacity 3.7.0 and do not change anything - the noise is gone.
So there is a bug in audacity 3.7.3. - I cannot see any other possibility. I also checked now other versions, the bug appears since version 3.7.2, until 3.7.1 I do not get any noise on the left channel.