I was approached once by a company that claimed to have an MIT-developed (or perhaps Bell Labs, it was a decade ago) fingerprinting technology that could recognize music or ad jingles in a fraction of the CPU required by Shazam. They wanted us to embed their mobile SDK into ours so they could track what people listen to what ads. Needless to say, we told them to take a hike, but I'm sure there are others that accepted the pitch. The apps embedding this may not even know. Fortunately microphone access now requires explicit permission.
I worked for a company that used a pattern matching algorithm and further licensed a fingerprint algorithm to do ID Ads and songs. (all pre-shazam) I can confirm we had a footprint in the wild with broadcast radio before 2002 doing the above.
