That's what I've been dreaming for ages!

I've been musing about a system/software that could listen on my PC's audio and control/adjust/mute the volume when it detects ads.

Such a system could also work for video content played on a PC!

This system could also be implemented on a dongle-like Raspberry Pi that would take the PC's audio output (3.5mm jack in/out), process the audio, and play back the "clean" audio to it's jack output: that could be seen as an audio firewall.

I think that working with analog audio (instead of official radio's streams) is the way to go to avoid legal issues: they cannot plug the "analog hole"!