Music Samples.
Freesound API is a free Music API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Details from freesound.org.

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Music Events
The Freesound API is provided by Freesound API documentation (freesound.org).
Yes. The Freesound API is listed in the Music category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Freesound API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the Freesound API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Freesound API is served over HTTPS, so it's safe to use in production.