I have an unnamed 4-port USB hub that usually works fine that has connected to it a Printer, Scanner, and Mouse. A problem occurs whenever I want to connect a fourth item, namely a digial camera card reader to upload pictures. I sometimes disconnect the hub and let it recycle. Reboot the system and find the optical mouse will not be powered. I removed the mouse from the port and left only the scanner and printer connected. Then when I connect the card reader it prevents the printer from working. What is going on? The individual hub lights are all on. Rebooting helps and/or disconnecting the power supply to the hub to recycle. I would like to be able to just connect the reader whenever I wanted to upload pictures. Do any other hubs work without the problems that I have described?