[martimaxin]

I just started experiencing problems with my power brick. It starts making noises when ever I put my ibook to sleep or shut it down. My batter is fully charged most of the time.

It's just a hissing noise that'd lead you to believe that it was going to blow up. I was scared initially, so I unplugged it and shut my laptop down.

Has anyone heard of this before?

[polendo]

I have heard that sound before, but not on an iBook. It was on an IBM laptop, but it came when it was plugged with the battery installed. As soon as the battery was uninstalled, and the laptop plugged in the noise went away. Have you tried taking out the battery and leave it plugged? - just to make sure is the brick and not a consequence of the battery.

[dracoleb]

That is somewhat odd. I know my adaptor sometimes gets hot, like I can't hold it for more than a second for fear of getting burned. Needless to say I’m replacing it.

[agentz]

Haven't heard an iBook PSU hissing but have heard plenty of Dell ones doing it (and not ones covered by the 4.4million unit recall!), however I've got two on my desk just now that have stopped working and only make a rapid ticking sound when plugged in.