Apple has just released a new bug-fix update with iTunes 12.4.2 that fixes random playback issues with Apple Music songs shorter than 60 seconds. The update is now available for Mac via App Store's Update tab and Windows as a direct download from Apple.
The Windows version of the update reportedly fixes three additional bugs including a security loophole, which could disclose sensitive user-information to unauthorised sources.
Coming back to the Apple Music bug, all tracks shorter than 60 seconds will play in its entirety and then the buffering for next track will start stalling as the song will never finish loading up for perpetual playback. However, this issue does not show up whenever any user decides to skip a song in the middle without completing its entire playback.
Here is a short release notes for iTunes 12.4.2 update from Apple:
This update resolves a playback issue with short Apple Music songs in your Up Next queue."
Check out the complete list of changes ported to iTunes 12.4.2 for Windows here.