Instead of being forced to re-boot my OS in order to have a different plugged-in USB device recognized, I'd like to know how to clear whatever so I don't have to do the re-boot. Here are the details:

Earlier this year I acquired a used, older IBM ThinkCentre desktop tower, machine 8143-2EU. It was built ~ 2004 and has a P4 cpu (64 bit). It came with WinXP loaded as sole OS. Before I wiped the WinXP and installed MEPIS 11, I tested the various USB ports. When I plugged in any USB device, the WinXP OS recognized the plugged-in USB device. But I wiped the WinXP, updated the IBM BIOS and installed MEPIS 11 (32 bit because MEPIS 11 only works with one variety of a 64 bit P4 cpu-- this desktop didn't have that particular variety). With the MEPIS 11 installed, I quickly found that no plugged-in USB device is recognized by the OS until I run in konsole:

Running that wakes up the OS and the plugged-in USB device is recognized and I can use it. But only 1 plugged-in USB device can be recognized and used at one time. To use another one, I first safely remove the recognized, plugged-in USB device and then I'm forced to re-boot the computer so that something is cleared and another USB device can be plugged in after the re-boot. If I don't do the re-boot and have another USB device plugged in, running lsusb still shows only the first USB device that was plugged in and recognized in a session.

In order to use another plugged-in USB device without re-booting, what command can I run to clear whatever so that I don't have to do the re-boot?

Incidentally, when I quickly discovered this problem earlier this year after installing MEPIS 11, I asked in various Linux forums how to correct the MEPIS-OS-failing-to-recognize-plugged-in-USB-devices problem but never found an answer. My theory is that something changed when I updated the IBM BIOS after installing MEPIS 11 (32 bit). I've examined the BIOS several times and see nothing to fix this problem.

An odd thing happens but rarely: a different USB device that's been plugged in is finally recognized by the OS but it can take many minutes before this happens. Why?

There are 2 USB ports on the front of the desktop tower and 6 in the back.

I've been using Linux for almost a decade and have had that problem countless times. It gets even worse in BSD. FreeBSD devs loathe USB with a passion and like to brag about it.

I kind of found a solution with Ubuntu. I don't know what it does, I just know that USB works a lot better for me on Ubuntu. Puppy Linux also does a great job with removable devices and hardware in general. So I recommend you try another distro instead of Mepis.

But even on Ubuntu, sometimes all USB ports become unresponsive if I plug and remove stuff more than a couple of times during a session. And I have to reboot to fix it.

Rebooting to fix the OS is great nostalgia, feels just like Windows 95 all over again.

I have run across the same issues with Mepis 11. I ran various versions of Mepis for years and am not impress with Mepis v.11. Within the the last three months I dumped using Mepis altogether and switched to Linux Mint. So far no major issues with the OS recognizing and connecting to any USB devices.