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iPod battery drain when connected to sleeping, off Macs part 2

iPod battery drain when connected to sleeping, off Macs part 2

We continue our investigation of battery-draining iPods connected to sleeping Macs, which has generated a huge amount of reader response. Some precursors regarding this issue:

As previously mentioned, Apple's documentation merely states that the iPod will not charge while the connected Mac is sleeping, not that the unit will discharge during this period of time. Knowledge Base article #61127 says "To charge iPod's battery, simply connect iPod to your Macintosh. The computer must be turned on, and iPod won't charge if the computer goes into sleep mode."

Most readers report that the iPod drains more quickly when it is connected to an off or sleeping Mac than if it is not connected and sitting idle (however, these measurements may be inaccurate - see below). Some have noticed that the iPod's hard drive sometimes spins while connected to a sleeping Mac. Thus it would appear that the iPod remains active while connected to a sleeping Mac, and is perhaps using more power to stay active than is being drawn from the FireWire port.

What's odd is that some readers have reported that the drain occurs even while an iPod is dock-connected to a Mac that is turned off. This would appear to indicate that that the iPod is constantly "listening" for a signal from the Dock, depleting its battery in the process. This notion is reinforced by the fact that it is not necessary to turn the iPod on when docking it for an update; even if the "hold" switch is active and the iPod is off, placing the unit in the dock will cause an automatic transfer.

For most, the discharge problem is not persistent, occurring once every few sleep sessions.

Some older models not affected Several readers have reported an absence of this problem with older (first and second generation) iPods connected via a FireWire cable; not the dock.

Ryan La Riviere writes: "I have a second generation (non-dock-based) 10GB iPod. I have, on several occasions, actually used my sleeping (and plugged into an outlet) TiBook to charge my iPod via Firewire. If I wanted to charge the iPod while the TiBook was not plugged into an outlet, the TiBook would have to be awake."

John Merritt writes "I have this problem with my wife's newer 10 GB iPod, but not with my older 10 GB, (pre-dock) iPod."

Another reader writes "I have noticed the same problem with my latest generation iPod but not my second generation iPod."

Using an external FireWire hub allows sleep charging Aside from simply using the AC adapter, the only way to continue charging some iPods while your Mac sleeps is to use an externally powered FireWire hub. This way you can still use a single connection for power and data transfer.

MacFixIt reader Eric Westby writes "I ended up using a powered FireWire hub to solve the problem -- since the hub continues to send power to the iPod/dock even when my G4 is asleep, the iPod is fully charged in the morning even though my G4 has spent the night asleep."

Battery measurement inaccurate? A note from reader Dan Martinez indicates that at least in some cases, while an iPod connected via FireWire to a Mac while it is sleeping may display a significantly lower battery capacity then prior to the sleep session, the actual playing time matches full capacity.

"While I've never had a complete discharge of the iPod I do notice that instead of the battery indicator reading a full charge, it in most instances demonstrates that the battery level is at about 2/3 the next morning morning. [...] What's even more interesting is that I can usually run the iPod in this 'uncharged' state for about 8 hours. It seems that the the battery indicator in the iPod (mine at least) is very unreliable and not indicative of what level of charge is really there. I don't know if this is directly related to the problem noted in the article. [...] When I charge the iPod with the AC adapter the battery indicator does appear to be accurate. I've never contacted Apple about this as I just chalked it up to a peculiarity since my iPod seems to have a pretty decent run time."

Another reader's experience also indicates inaccurate battery readings:

"An issue that I've also noticed is that after recharging the battery icon takes some time before it shows the actual state of charge, it seems to need a few minutes before it shows fully charged. I can live with this one but not the other."

Slow charging because of other devices A separate , but possibly related issue that has popped up: slow charging when other FireWire devices are connected. Bob Sutryk writes:

"One other issue that frustrated me for months: Shortly after I put Mac OS X 10.3 on my computer the iPod seemed outrageously slow to charge. After months of dealing with this and sending the iPod in to be fixed, a sharp Apple tech finally discovered that my iSight camera was pulling too much power for both Firewire appliances to handle. Once I unhooked the iSight, the iPod ran like new."

Our report yesterday contained a statement from an "Apple Product Specialist "claiming that when the iPod is docked, it continues to drain the battery even if both the Mac and the iPod are in sleep mode because the iPod consumes power at a greater rate than if it were not docked; charging much more quickly when attached to the AC adapter. So it stands to reason that iPods may also discharge more slowly if they are the only connected FireWire device.

Have you experienced faster charging, or slower discharging of a docked iPod when other FireWire devices are connected? Drop us a line at

AC adaptor may more fully charge iPod batteries Besides not discharging, the iPod AC adaptor may be able to more fully charge an iPod battery relative to the dock in some cases.

"I have a 10GB second generation iPod. I normally charge by hooking the iPod to my laptop or desktop. Around early Jan of this year it would appear that my iPod would not hold a charge. When hooked up to a computer it would seem like it could never reach full charge on the display. If it did, then it wouldn't hold its charge for more than a couple of hours. I thought the battery was toast. On a fluke, I connected it to the wall charger. After it reached full charge, I was again able to get about 8 hours of playing time. Its like having a new iPod!"

Setting startup time to three hours prior for maximum charge Knowledge Base article #61127 also notes that the iPod is "80 percent charged in about an hour, and fully charged in about 3 hours."

If you want to keep your iPod docked overnight (or for another long, unattended period of time), you can use a utility like iBeeZz to automatically wake your Mac up three hours before you'd like to begin using the iPod. This will provide a full charge - based on Apple's claims - in spite of discharging.

Mac freezes when going to sleep with iPod connected Another problem with charging from the dock, noted in Apple Knowledge Base article #60929, is that "your computer may stop responding ('freeze') if it goes to sleep with an iPod connected to it."

The only suggested resolutions for this issue are:

  • Restart your Mac
  • Turn off sleep in Energy Saver
  • "Do not put your Mac to sleep when the iPod is connected"

  • #61127
  • iBeeZz
  • #60929
  • More from Late-Breakers