I want to record skype calls. If I use the speakers and the notebook microphone, then the result is good. However I usually use headphones or headsets to call on skype and, if I use this, than I can listen only strange buzz from the recorded file.
I’m running Debian Jessie with Audacity 2.0.6 installed from the official debian repositories.
Because of the way Skype works, we usually push Windows users off to a software application designed to do that.
I can well imagine that in the first case what was really happening was you were recording the computer’s microphone, not Skype. Since the speakers were active, that’s how Audacity captured both sides of the conversation. The instant you plugged the headphones in, that sound pathway vanished. I bet the receive sound at the far side was much clearer when you did that. Skype didn’t need to do real-time echo cancellation…at all.
The system still records your own voice, right?
All that is normal. I think your only hope is finding a Linux application that “knows” about Skype.
You don’t say what app you are recording with. The simplest solution is usually to use Skype Call Recorder. Audacity was not explicitly designed to record VoIP calls.