In the new Betas, there was new Nether Music and sounds. But I cannot head any of these. I've played there sound files and put in the Music Disc for Pigstep. But no sound will play at all. This has happened since the addition of these sounds. And yes, I had downloaded the free music pack from the marketplace, but nothing has changed...
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Thank you for your report!
We're actually already tracking this issue at MCPE-69271, so I will resolve and link this ticket as a duplicate.
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