I recently uploaded a project to one of my side accounts which featured a little music I made with the note blocks.

However, when I uploaded it, the notes were shorted, and sounded awful.

What happened?

Scratch 1.4 uses MIDI sounds for their note blocks, and the computer's MIDI music library had a lot of sounds to choose from.

Scratch 2.0 runs in Flash, and Flash doesn't have MIDI support. The result is that the ST had to create their own music library for the note blocks, which, admittedly, sounds horrendous and is very incomplete. Getting a better music library for 2.0 is on the to-do list.