Hey, at least mine’s connecting at all! 
Also, USB 1.1 can do 12Mbit/s, that’s plenty for audio data.
aplay -l says this:
**** List of PLAYBACK Hardware Devices ****
card 1: Sprout100 [Sprout100], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
So not very helpful with regards to USB 1 vs. 2. I’ve never had a problem with dropouts, though.