If there is unwanted noise (static perhaps or a barking dog) in the audio you're using in your eLearning projects, all of the eLearning tools allow you to quickly edit the audio file and delete the offending noise.
However, if you come across audio gaffes between segments of your waveform, it may not always be appropriate to simply delete them. Sometimes deleting parts of a waveform shortens the segments between two waves and has a negative effect on the timing for the rest of the audio. In those instances, it's a better idea to convert the gaffes into silence.
Fortunately, if you're using any of the top eLearning development tools, the ability to replace portions of an audio file with silence is built-in... and the process is similar no matter the tool.
For instance, if you're using Adobe Captivate, choose Audio > Edit > Slide. Highlight the part of the waveform you want to replace with silence and then click Insert Silence.
In Articulate Storyline, select the audio object on the Timeline and, on the Ribbon, select the Audio Tools Options tab. Then click Audio Editor. As with Captivate, you simply need to select the part of the waveform that you want to replace with silence and then click Silence.
In TechSmith Camtasia Studio, choose Tools > Audio, select a segment of the waveform on the Timeline, and then from the Volume group, click Silence.
Last, but not least, if you're a Lectora user, visit the Home tab on the Ribbon, select a segment of the waveform and from the Volume group, click Insert Silence.