1. Open Impress
2. Select a shape/box
3. Sidebar - Animation - Add: Random Effects
4. Options - Sound (select a sound)
5. Start slideshow or preview
Already in 3.3.0 on Win 10 (tested 4.3.0 as well). Bogdan found this issue.
Arch Linux 64-bit
Build ID: d559c28e9e65f3be415ec2e36ee90aa147e65b84
CPU threads: 8; OS: Linux 4.20; UI render: default; VCL: gtk3;
Locale: fi-FI (fi_FI.UTF-8); UI-Language: en-US
Built on 1 March 2019
On pc Debian x86-64 with master sources updated today, I could reproduce this.