Stuttering sound in 1.1.90 when opening projects from sidebar while playing (windows/SDL)

Trying out the new 1.1.90 I noticed that I get the sound of a buffer being looped when I open a project from the sidebar and the "version mismatch" dialog appears. This doesn't happen when opening from the recent files list or going through the "open project" dialog, so I'm guessing there's a code path that would need playback to be stopped or a buffer to be cleared after stopping.

Tested Windows Vista 32-bit and Windows 10 64-bit, looks like this only happens using SDL.

Somewhat related discussion in #1384.

Reproduce the issue on Windows with SDL by opening a project from the sidebar while playback is active and the version-mismatch dialog appears. Compare that path with opening from recent files or the open-project dialog; done means the buffer no longer loops after the dialog appears.

Written by the indexing model from the issue text.