:~$ uname -a
Linux dante 2.6.22-14-generic #1 SMP Sun Oct 14 23:05:12 GMT 2007 i586 GNU/Linux
:~/line6/line6usb-0.7.3$ sudo make install
make -C /lib/modules/2.6.22-14-generic/build SUBDIRS=/home/jose/line6/line6usb-0.7.3 modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.22-14-generic'
Building modules, stage 2.
MODPOST 1 modules
make[1]: Leaving directory `/usr/src/linux-headers-2.6.22-14-generic'
mkdir -p /lib/modules/2.6.22-14-generic/kernel/sound/usb
cp line6usb.ko /lib/modules/2.6.22-14-generic/kernel/sound/usb
mkdir -p /usr/bin
cp *.sh *.pl /usr/bin
/sbin/depmod -a
/sbin/modprobe line6usb
:~/line6/line6usb-0.7.3$ dmesg | grep -B2 -A2 line6
[ 1039.609063] usb 2-1: new full speed USB device using uhci_hcd and address 4
[ 1039.789020] usb 2-1: configuration #1 chosen from 1 choice
[ 1039.791695] line6usb 2-1:1.0: Line6 TonePort UX2 found
[ 1039.791724] /build/buildd/linux-source-2.6.22-2.6.22/drivers/usb/core/message.c: selecting invalid altsetting 5
[ 1039.791746] line6usb 2-1:1.0: set_interface failed
[ 1039.791783] line6usb: probe of 2-1:1.0 failed with error -22
[ 1039.792436] line6usb 2-1:1.1: Line6 TonePort UX2 found
[ 1039.792458] /build/buildd/linux-source-2.6.22-2.6.22/drivers/usb/core/message.c: selecting invalid altsetting 5
[ 1039.792480] line6usb 2-1:1.1: set_interface failed
[ 1039.792508] line6usb: probe of 2-1:1.1 failed with error -22
[ 4795.381233] Clocksource tsc unstable (delta = 96030962 ns)
[ 4795.385213] Time: pit clocksource has been installed.
Logged In: YES
user_id=2061888
Originator: NO
You are getting the "set_interface failed" message because the Line6 TonePort UX2 is currently unsupported by the line6usb driver.