I have a similar system, and had the same problem. I found that the problem was caused by an externally powered usb hub. I can only assume that surges or dips in the power caused the hub to momentarily loose the connection.
At irregular intervals & several times per day, my PC makes the USB connect / disconnect sound. (WinXP SP2, AMD Athlon 64 3400+, 1 GB RAM)
I can't find out which device actually connects and disconnects.
I tried to follow the events in the Device Manager, but when the connect / disconnect eventually occurs, the Device Manager refreshes and goes back to the top of the list of devices. Unfortunately, the USB devices are not at the top of the list ![]()
Even if I could see the interesting part of the list, I wonder if I'd have the time to actually recognise the device - it happens so fast. It's quite frustrating...
I thought Windows might provide a log of connects / disconnects, but found not such information, neither in Windows Help nor on the web.
I searched the web for a log utility and found none.
=> Any ideas ? Thanks for your help!

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