I was mining on my survival with a silk touch pickaxe, and I got a few redstone ore. Later to get the redstone I put down few to break it, but sometimes it didn't made any sound.

What I expected to happen was...:
I was expecting that the block would make a sound

What actually happened was...:
Sometimes it made a sound, sometimes it isn't.

Steps to Reproduce:
1. Just put down a few redstone ore.
2. ...
3. ...