This is my opinion only, I'm not a Knoppix guru:

I think your options are:

1. Fixing it yourself: While the USB 2 problem is not too difficult to fix (see earlier posting), I think the USB 1.1 fix (for Asus A7N) i.e. kernel rebuild and remaster is not worth the effort.

2. Go back to a Knoppix 3.x version, which worked fine. Wait for next release of Knoppix.

3. Unplug the memory chip reader, or whatever USB device is causing the problem. This is not a good solution if the device is internal to your computer. You could use an external chip reader and plug it in when you need it.

4. Change to Kubuntu, while waiting for the next release of Knoppix. I found that everything I need works in Ubuntu/Kubuntu (for the Asus A7N266 motherboard).