Ubuntu Studio (20.04): studio-controls has unexpectedly stopped working

Question

Running Xubuntu 20.04.4 LTS. Ubuntu Studio installed via ubuntustudio-installer with backports activated. For several months I've been running studio-controls without problem. Yesterday it ran fine. Today it doesn't but generates the following when run in a terminal:

$ studio-controls
install path: /usr
Config file: /home/user/.config/autojack/autojack.json
Traceback (most recent call last):
  File "/usr/bin/studio-controls", line 1881, in <module>
    us = StudioControls()
  File "/usr/bin/studio-controls", line 623, in __init__
    self.refresh_net(self.znetbridge)
  File "/usr/bin/studio-controls", line 1494, in refresh_net
    if not (os.path.isfile(znj) and os.access(znj, os.X_OK)):
  File "/usr/lib/python3.8/genericpath.py", line 30, in isfile
    st = os.stat(path)
TypeError: stat: path should be string, bytes, os.PathLike or integer, not NoneType
$

Never had this problem before. Any ideas? Any further information needed?

Answer 1

Using Synpatic Package Manager, I removed studio-controls. Synaptic informed me that it will also remove ubuntustudio-installer. After removing those two packages. I then reinstalled ubuntustudio-installer. Installing ubuntustudio-installer also installs studio-controls. Then I executed studio-controls, which now worked as expected. All is well.