I find this kind of confusing, but here the gist the way I understand it.
Digital Music Express (DMX) has been around for decades as a competitor to Muzak, Music Choice and Galaxie in Canada. DMX was the digital audio provider that Primestar used and they were on some smaller cable systems. In the early 2000s a new company called Mood Media came to be. Mood Media specialized in digital signage and other touchy feely marketing type crap used to draw people into retail businesses. Mood bought out DMX at some point, and then around 2010, Mood bought out Muzak. It seems like they are two unique services with their own unique line ups that happen to now be owned by the same company. Similar like how Sirius and XM had their own lineups still in place for a while after the merger before they combined.
Why DMX on DirecTV was branded as Sonic Tap, I have no idea, but in looking online, I have seen the DMX line up on small cable systems, and maybe in Canada as well. It wasn't the 80+ channel lineup DirecTV had, but it was called DMX, not Sonic Tap. And I don't believe DirecTV got the full DMX line up. Looking on their website, they had a bunch of channels not on DirecTV.
I cannot find specific examples, but I'd be willing to bet, there are some cable systems of small fiber based TV systems around the country that still use DMX. Like with similar services, these are programmed for retail and commercial environments. I'm convinced the only reason satellite and cable cos make them available to residential subscribers is to inflate channel count numbers. Mood Media seems focused on custom music mixes for specific retail chains..
