Is it possible to do realtime noise-removal with PulseAudio, so the sound output that's coming out is smoother?
Investigation shows that there is no known way of doing real time noise reduction filtering with any Linux sub system. Some websites point to hardware you can buy which should do the trick much better than doing a software filter.
Alternatively if this is for a recording, you could pass the sound through Audacity and use the noise filter there.
Here's at leas tone way, implement webrtc-aec in the
webrtc-aec Yes Uses the webrtc.org AudioProcessing library for enhancing VoIP calls greatly in applications that support it by performing acoustic echo cancellation, analog gain control, noise suppression and other processing.
Here's a paper dated 2013 on the subject (noise removal with pulseaudio not webrtc-aec specifically) http://lac.linuxaudio.org/2013/papers/37.pdf
"We have presented rst results of a multi-channel noise/echo reduction solution built on top of PulseAudio and motivated the design decisions. The work has resulted in a number of improvements in the PulseAudio echo cancellation and signal-processing framework, which have been contributed during the version 3.0/4.0 development cycle and should facilitate future embedded Linux audio solutions. Further work includes optimizing code for audio stream mixing, more ecient resampling methods, and the implementation of an efficient AEC in the multi-channel processing pipeline."