Voiceovers clips are added to video and suddenly become garbled

[Hooleyan]

As I go in and add voiceovers to my video on timeline everything works fine.  I move down timeline and record another voiceover without adjusting anything on microphone or PPro and voiceovers become garbled.  I went in and deleted all my media cache files and that appeared to fix it but within a couple of additional clips the voiceover becomes garbled again.  My first few videos were no problems and now I encounter this issue everytime I produce a video and it is getting pretty maddening as it seems like a simple process.  I have a very new computer built specifically to do videos and it never crashes or freezes and renders very quickly so I'm lost as to what is causing this.  Thanks in advance.

[Ann Bens]

When not using the mic; make sure Default Input in the Audio Hardware in the Preferences is set to No Input.

[Hooleyan]

Thank you for responding. I will try that.