I am using my re-badged Litey at work (Memorex external) and it works great. My only complaint is that, since it is my work computer, I can’t upgrade the USB to 2.0, I’m stuck with 4x burning on the 1.1 USB that came with the 'puter (I have to upgrade mine at home, too, though). Anyway, I can get Kprobe to work fine. One problem I found was that I like to listen to the online radio and that messes up the scans. The new Prodiscs I bought looked like they were burning like crap, based on Kprobe’s results (widely variable C1 errors, between 20 and 300, C2 errors varying from 1 to 30+). Turned off Media Player and re-tested them, there was a 150% turn around in results, they looked great (very low C1 errors, no C2 errors). Perhaps when you run Kprobe, you should shutdown all other programs and give it a shot.
Oops, re-read your post which said that you are trying while running nothing but Kprobe. The only thing I can suggest is that you try running Kprobe on a disc on your ext. drive, then take that same disc and run the test using an internal drive and compare the results. If the red spikes are not on the graph for the internal drive and the error rates look to be similar, then just ignore the spikes when they show up on the external drive. Alternatively, if you have a USB 1.1 port on your computer, try running the drive on that port while using Kprobe and check those results against what you are getting using the USB 2.0 port.