[BUG] Disconnecting Machine without closing AYAB app results in the app not responding

[Dee-the-Dee]

Environment
AYAB software version: 1.0 Beta
Computer/OS: Windows
Knitting machine: KH910
AYAB hardware: Shield 1.4

Describe the bug
Disconnecting Machine without closing AYAB app hangs the app and needs to be killed from task manager

To Reproduce
Steps to reproduce the behavior:

1. Connect machine to computer with USB
2. Open AYAB App
3. Disconnect the USB from the computer ( while the AYAB app is open )
4. Try to close the AYAB app
5. App has stopped responding. To close the app it has to be killed from the task manager

Expected behavior
App should close

Screenshots

Additional context

[dl1com]

also see #228 and #194

[jonathanperret]

Ah good catch @dl1com — my bad for not suggesting to @Dee-the-Dee that the issue might already have been reported.

[jonathanperret]

Although #194 is closed as completed and #228 as a duplicate, and yet the issue currently happens in 1.0 beta 4, so I suggest we keep this open.