hdajackretask creates a script in /tmp before executing it. When /tmp is mounted with noexec, running that script will fail, but the GUI gives no indication that it failed.
I'm on Ubuntu 18.04.5, with alsa-tools-gui package version 1.1.3-1.
The GUI should check for the exit code of the script, and notify the user appropriately if the script failed to execute.
Also, if this isn't the appropriate place to report a bug, please let me know!