Hi there! I’ve come to these forums a lot via Google when investigating various issues and they have been immensely helpful, but all my searching has not been able to help me with this one - I use a Zoom H4N with an ATR2100 to record my show (but started having this same issue with my ATR 2100 plugged into my Dell Inspiron Laptop prior to buying the Zoom). And I’ve found that there’s this strange underlying hum that Noise Reduction doesn’t take out because it’s under the words as well, and it doesn’t happen the entire time - I record a podcast that is anywhere from 25 - 45 minutes, and the hum usually starts at some point after 15 minutes in, and sometimes stops before the end of the show.
I apply noise reduction (using the ten or so seconds I leave silent at the beginning of the record), normalization, and a noise gate. I tried fiddling with the notch filter and couldn’t get it to do anything meaningful for this issue.
This happened on the version of Audacity I was using before, but now I am using 2.4.2 on Windows 10.
I’ve attached an audio clip where you can hear that it was not happening for the first 5 seconds (and prior 25 or so minutes), and then suddenly started happening and continued through the next 10 minutes or so of recording.
I am truly at a loss, so any suggestions would be much appreciated. I think what throws me off the most is that it doesn’t do it the whole time, so something I’m unaware of is changing at some point in the file/recording.