In the past if you wanted to “broadcast” live audio to learners you basically had to be the BBC or use a CB radio. The challenge was that the learner who was listening needed a receiver at their end.
The internet now makes it much easier to broadcast live audio using tools such as Nicecast.
Nicecast is the easiest way to broadcast music from your Mac. Broadcast to listeners around the world.
The thing about Nicecast is that the stream is a simple URL. For learners this is not always that simple, for example they may lose, delete or be unable to find the e-mail that contains the URL. If printed on a handout may contain an error, or the learner may type it into their browser wrong.
Putting the URL, or even better embedding the live audio feed into the VLE will ensure that learners can not only find the feed, but also listen to it whenever the practitioner broadcasts. To be honest you probably want to e-mail the URL anyhow and any other communication channels that the learners use, Twitter for example.
The VLE is only really one medium and reliance on any one medium is not good practice. However though if the VLE is used regularly for posting these kinds of feeds and links, then the learners will become familiar with going to the VLE to access them.