[cups] oki432 laserprinter ready to print but doesn't print (anymore)

[mh]

Hi,

after working flawlessly for the last years (on Debian / sid(uction) aka
unstable, up to date), cups now has problems to send the job. The
printer seems occupied 

(verarbeitet seit Di 17 Nov 2020 15:22:03 CET 
"Warte darauf dass der Drucker verfügbar wird."
= EN: "waiting for the printer being available");

at the same time the printer shows "Ready to print".

I can print from a live cd, though. I take as an indication that
both the printer and the cable are ok.
 
On this installtion however the job sometimes gets printed while the
computer is shutting down.

I tried to purge cups and reinstall afterwards to no avail.


This is what I found out so far:
# lsusb
Bus 002 Device 005: ID 093a:2521 Pixart Imaging, Inc. Optical Mouse
Bus 002 Device 004: ID 05e3:0608 Genesys Logic, Inc. Hub
Bus 002 Device 003: ID 2040:0265 Hauppauge WinTV-dualHD DVB
Bus 002 Device 002: ID 06bc:0357 Oki Data Corp. USB Device <-- my
printer
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub




***************
# /usr/lib/cups/backend/usb
DEBUG: Loading USB quirks from "/usr/share/cups/usb".
DEBUG: Loaded 95 quirks.
DEBUG: list_devices
DEBUG: libusb_get_device_list=9
DEBUG: Failed to detach "usblp" module from 06bc:0357
***************
I do not understand the consequences of this error


***************
# lpinfo -v
file cups-brf:/
network lpd
network socket
serial serial:/dev/ttyS0?baud=115200
network beh
network ipp
network ipps
network http
network https
direct parallel:/dev/lp0
network smb
**************

Any advice on how to get this printer working again on this system
would be highly appreciated.

Thanks

Michael