For a long time time I've been trying to get rid of the background noise that appears in every audio recording I make with my computer. Tried different microphones, different sound setting, drivers.
Interesting fact - the volume of this sound is equal whether I use and internal notebook microphone or an external one. I tried really good mics, so I'm sure the problem is not in it.
Laptop on which this problem appears in HP Probook 4720. OS - Windows 7.
P.S. Read an answer to a similar question: Annoying sound from microphone in headphone. Tried everything that was mentioned there. Only I don't have a "DC Offset Cancellation option". And when I disable "Noise Suppression" and "Acoustic Echo Cancellation", noise only becomes more noticeable.
What should I do?
EDIT: Example of the background noise I'm describing: http://eos-soft.com/files/noise.wma.