I had an issue like this, but it was for a scanner. I wound up finding on the qemu forums a gent who advised to do the following, note it worked for me your mileage may vary:
A note of caution: I have read an old security advisory, but cannot confirm if this is still a potential security risk or not. I by no means am a security expert. I found along my travels a note of something to the effect that SuSe had a security advisory regarding this, however, even as of 10.1 GM they still had this in their fstab as default. So I'm thinking ? and cannot be sure that some how maybe ? this got fixed in a patch somewhere along the lines.
But like I said it worked for me.
First: let's say you have group number 120 available, then:
Secondly, you add a usbfs in /etc/fstab:
none /proc/bus/usb usbfs defaults,devgid=120,devmode=0664 0 0
now add your user into group 'usb', you can do it with pico as root in cli
then as a test, simply
see if you get any goofball error's or not.
if not reboot and you should be good to go. that should "git er' done" (TM)