I recently purchased an Iomega Predator CD-RW and an ADS Technologies Ultra
Hub 4-port externally powered USB hub for use at home with my slot-loading
iMac 350 (OS9.2.2). The software install went perfectly and the program
works exactly as expected. Not a single freeze or hiccup. I used them over
the next several days to burn a handful of audio CD's and a couple of backup
data CD's with no apparent issues. Then, about 5 days later on every
startup, the iMac volume would insist on being set near 3/4 of full volume.
I would turn it down or mute it before shutdown, but it would return to that
high level on every subsequent startup. I didn't do a PRAM reset or
otherwise spend any time debugging that quirk, considering it as just an
annoyance for the time being.
Then after about a week and a half, the iMac completely shut down while
surfing the 'Net and would not power back up at all. Just clicked off like
the power plug had been pulled. I've checked all the cords, plugs, went
through the hard reset steps, and determined with a multimeter that there is
power all the way up to the iMac plug in the back of the machine. I've
finally taken it in to my local shop and been given the bad news: both the
analog board and the logic board are no longer functioning. The service
manager asked if the machine had failed during a lighting storm, or if there
had been any other forms of a power surge in the neighborhood - there had
not.
Since lightning is a frequent problem here and the residential wiring in
coastal Florida is constantly under attack by the salt air environment, we
often see power surges and "brownouts" and occasionally a complete power
outage. So for several years now I've used two surge protected power strips
in the circuit before the iMac and the peripherals see any power. Even the
phone line is protected this way. Only the Ethernet broadband cable
connection does not run through this buffer, although it also serves cable
TV to the rest of the house. I've felt this was a pretty good arrangement,
although I have never had any of the protectors trip or blow a fuse yet.
So I wonder: it seems unlikely that the new CD-RW and hub are responsible
for this failure since they appeared to operate properly for several hours,
and still appear to power up normally. Could this just be cumulative
low-level damage that has been suffered over time and just a coincidence
that it has failed at a time when I added new equipment? Maybe I should have
more sensitive surge protection devices? Or, are there any known or
suspected issues with these devices concerning power management or leakage
back to the iMac through the USB ports?
Anybody care to speculate? Ever heard of a USB peripheral toasting the host
circuitry? Since I'm looking at a repair bill approaching $500 (I know, I
know, I can buy a used machine for less), I'm hesitant to just have it fixed
and plug everything back in, or even trying to plug these in to another
system as a troubleshooting approach. Any thoughts would be much
appreciated.
Thanks!
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