Hi,
first time poster and not sure if it fits in this empty category: When trying to use the extension board RTL-SDR device with the stock firmware or Bookworm 6-12-y I got the error
"usb_open error -3 Please fix the device permissions, e.g. by installing the udev rules file rtl-sdr.rules"
Turns out it is missing a udev ruleset for non-root users for some reason. With the help of tutorial Rtl-sdr on Ubuntu : 4 Steps - Instructables
I sudo nano’ed a new file /etc/udev/rules.d/20.rtlsdr.rules with content
SUBSYSTEM=="usb",ATTRS{idVendor}=="0bda",ATTRS{idProduct}=="2838",GROUP="adm",MODE="0666",SYMLINK+="rtl_sdr"
which fixed it – in case someone has the same problem.
Best
Michael