Certain USB hubs could cause system instability on Macs

Well, in reality, Apple can't control the quality of 3rd-party hubs and peripherals.

Apple cann't really be expected to be held liable for your USB tentacle monster. In the case of a laptop Mac, simply wake the machine using the on-system keyboard and/or by opening the lid.

Personally, I have been telling people for years that mouse and keyboard should always be directly connected to USB ports. never through a hub. if the driver for the hub disappears for whatever reason... let's just say, you better be very adept at using the Tab key...
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http://www.WiredBuddha.com

I've purchased cheap and expensive USB hubs that both work sometimes and also sometimes give peripherals problems. But most problems disappeared when simply never putting my computer to sleep anymore. So now it's either on or off.

I remember the SCSI problems of daisy chaining and how much of a pain it was to keep drives working properly. The same seems to be true with firewire where certain daisy-chained drives only work in one particular order. I just hope newer ports as Thunderbolt and the like fix some of these finicky connection issues.

For those still having problems after heeding all the advice, there's an independent USB driver that many people like called USB Overdrive. For me, not having problems, it just added complexity, but if you're having problems or want an additional level of control, you might find it worth a look.

http://www.usboverdrive.com/USBOverdrive/News.html

Of course based on Apple's advice, maybe my Mac Pro should have more than 4 ports on the back!!! Kind of silly to expect a machine with 3 internal HD's, 8 processor cores, multiple graphics card/etc, 2 DVD burners, to only need 4 USB devices (and since I use a cinema display I get a few more ports that way). Because a color printer, scanner, mouse, keyboard, iPad/iPhone, digital camera, video camera would be an unexpected number of devices for a machine of this class???

A similar issue - I have one of these USB HD docks and I recently found that if I forget to turn it off, my half-year-old iMac hangs on reboot. My guess is that the Mac firmware is trying to enumerate all attached drives, and because there's no actual HD plugged in to it, it gets stuck.

So it's not just me.

I have a Kensington hub that I like but it recently became weird, hardly able to keep things connected or let new things connect. So I switched to another hub, though weird things sometimes happen with it too.

I put my screen to sleep at night, and since I have a 27" iMac I am apparently 'required' to go out of my way to get this screen to come back on. My way of doing this without restarting is to put the computer to sleep then wake it up with a click and wild movements of my (Bluetooth) Magic Mouse. (My keyboard's also Bluetooth). Maybe this constant sleep/waking is causing my USB problem.

Plus, connecting my iPhone sometimes kicks my external USB drive out of Finder, even though the iPhone connects directly to the iMac and the drive is connected to the hub...

When did USB start just not working?

The above is all good advice, all of which I've learned in other ways over the years.
- give preference to FireWire (and now Thunderbolt) to USB
- use Bluetooth where possible, though wireless USB generally outperforms it
- use powered hubs exclusively
- don't daisy-chain hubs (note: all large hubs are internally daisy-chained)

I've found the Microsoft InteliType and InteliPoint drivers to cause kernel panics on several of my systems across several versions of OS X. On my brand new iMac last summer I had near weekly panics until I removed them. I've had no panics since —224 days today ;-)

I have the opposite problem. My mac mini turns on automatically every day and had everything hooked up directly. It would randomly eject my two USB drives which caused a lot of grief.

After searching around on forums I found others with the same problem - and a solution: Plug the two drives in a hub. I used a non-powered one. Been running perfectly ever since.