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As MuvAudio records from the soundcard as other applications play audio, there is a good chance that it is picking up noise from analogue sources such as the microphone and line-in sockets regardless of whether any cable is physically plugged into these.
Probably the simplest check you can do is go into your Soundcardâ€™s recording features and mute everything except â€˜Waveâ€™. To do this, perform the following steps (for most soundcards):
[li]Double-click the small speaker in the bottom-right tasktray to bring up the audio mixer.
[/li][li]Click the â€˜Optionsâ€™ menu -> â€˜Propertiesâ€™.
[/li][li]Tick â€˜Recordingâ€™, check every box you see in the selection below and click OK.
[/li][li]For the far left master recording volume control, drag the slider up to max.
[/li][li]If the selectors show a â€˜Selectâ€™ tick box beside them, only tick the selector with â€˜Waveâ€™. Otherwise, if the selectors show a â€˜Muteâ€™ tick beside them, mute them all but the â€˜Waveâ€™ slider. Drag the â€˜Waveâ€™ slider up to max also.
[/li][li]Now, attempt to make a recording. If the recording comes out distorted (like a volume too high clipping sound), then drag both the â€˜Waveâ€™ and â€˜Master Recordingâ€™ sliders to the middle and try again.
If you donâ€™t see a â€˜Waveâ€™ slider in the recording volume control, then choose â€˜Stereo Mixâ€™ and drag its slider to max. If this is the case, you will need to bring up the standard playback mixer and mute everything except the master and â€˜Waveâ€™ sliders.
Unfortunately, it is difficult for me to provide steps that covers all soundcards, as each model and make of soundcard has different volume control sliders for both playback and recording. Some soundcards also only allow you to make adjustments using their own control panel. For example, the 3rd party kX Project drivers I use for my Creative soundcard only offers a few controls in the standard windows mixer, but offers a huge range of volume controls including a sophisticated virtual studio-like mixing desk in its own control panel.