I imported an MP3 file to attempt noise reduction on. After selecting a sample and performing the Get Noise Sample step, I tried to do a Preview before performing the actual noise reduction.
The first time I did this, I selected the entire track (approximately 25 minutes) then Effect > Noise Reduction > Preview. The remaining time listed in the pop-up kept increasing, so eventually I cancelled the process. Then I selected a smaller section of track (less than 2 minutes) and went through the same process. I left my computer for 5 1/2 hours, and the preview never went anywhere. The time remaining just kept increasing.
Since I have the original file elsewhere, I decided to select the whole track and simply perform the noise reduction on it without previewing. Audacity finished this in less time than it has taken me to type in this post.
So it’s not my computer, since it handled the actual noise reduction in mere seconds (and it turned out beautifully). Is this a bug?
I would really like to get the preview function to work. (Great software by the way.)