When creating a new ticket and when asking questions on the mailing list or IRC about a problem with using libusb it is important to include all the information that is needed for the library developers to understand your environment and what your program is doing.
A libusb debug log will often contain very valuable information and may in fact be sufficient to discover exactly what the current problem is. It is also helpful for the developers if you try to reproduce your problem with the very latest code in libusb.git. Here is a very simple way to test your program with a debug-enabled build of libusb on a Linux system, without affecting any files that are installed by the distribution package manager:
git clone http://git.libusb.org/libusb.git cd libusb ./autogen.sh --prefix="$PWD/usr" make install LD_LIBRARY_PATH="$PWD/usr/lib" /usr/bin/lsusb 2> debuglog.txt
Replace /usr/bin/lsusb with the application that you would like to test.