USB driver 'uninstalling' themselves???

Ive got a problem with my plug-in usb devices in that every time i plug them in, the computer acts as though it is the first time it has seen them!! I then have to wait or a minute or so while windows finds the drivers for them.

They are - Bluetooth dongle, Memory card reader, even my camera is playing up now!!

Anyone got any ideas why this is happening?? Please help as im getting close to launching said peripherals out of the nearest window.............

This always happens with my computer as I use XP Pro fully updated.
If you are using a older OS than it takes a bit longer for it to find it every time.
A slow computer can REALLY put a hamper on this also.
However this sounds like normal behavior to me.