this sounds like Realtek HD Sound Effect Manager!
this should be in control panel - (Switch view by large icons) Realtek Audio manager -> make sure it is set to none.
If the fault persists it might be worth while just installing the latest driver from realtek. http://www.realtek.com.tw/
click High Definition Audio Codecs (Software)if your running 32 bit os
32bits Vista, Windows7, Windows8 Driver only (Executable file) R2.70 if your running 64 bit os
64bits Vista, Windows7, Windows8 Driver only (Executable file) R2.70
If this doesnt sort then its likely you have a hardware fault.