.51 Several issues with Instrument tree "delete&a

[Saga Musix]

Full Version:
OpenMPT v1.17.02.51

Has the bug occured in previous versions? If yes, please specify version(s): (This option is optional, and doesn't need research. But in case you know...)
yep

Description of the bug:
Issue one: If you want to delete an instrument, you get the prompt "remove this sample?". During that prompt, the playback buffer is not updated, but still played. you'll hear a buzzing sound from the sound that's still in the buffer.
Issue two: Even if you click "no", your instrument gets trashed!!!

EDIT: Can't reproduce that one anymore, setting it to "closed".