I just ran into this bug last week and it took me a while to find the workaround (other than convincing Microsoft that they needed to fix their Win8 built in USB recording drivers!).
Do the following:
- Make sure OmniMic isn't running.
- Find the Omnimic.exe file (probably in C:\Program Files\OmniMic or C:\Program Files(x86)\OmniMic) with the file browser, and right-click on its file name.*
- Then choose "Properties" from the menu that appears
- Then click on the tab labelled "Compatibility", in the "Compatibility mode" box select "Windows XP (Service Pack 3) and put a check in the checkbox labelled "Run this program in compatibility mode for:"
* (You can instead do this process for any icon or menu shortcut that you use to start OmniMic, but then it would only apply the fix when you run OM that way).
Then you can use OmniMic normally.
I have no idea why this happens in Windows8.
From Google searching I see that people have been having the same problems with other USB microphone or recording hardware in Win8. I suspect it is a bug in Win8 rather than some "feature", as the effect in normal audio programs of it is to throw away about 4 bits of resolution and make recording seem very weak".
(It might be a good idea to do this also with any programs you have that you use with USB microphones or similar functionality.)