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I really hope we get a fix for this from Apple, whatever the problem may be ...

I don't have anything to back this up, but I'm curious as to how many different Airport cards have been used in the different models over the last few years.
Maybe driver issues are finally starting to catch up with Apple a little.
*Repeat - pure speculation on my part again but it kind of makes sense as to why certain updates improve the connection and others don't.
 
I had this problem after upgrading to 10.5.8. My MBP would not play nice with WiFi on battery, plug her back in and all was well. I found many many people on Apple discussion forums with same issue, so in the end following the instructions in this blog post and voila, Wi-Fi back.

http://blog.hep-cat.de/?p=4760#Mac
 
I had this problem after upgrading to 10.5.8. My MBP would not play nice with WiFi on battery, plug her back in and all was well. I found many many people on Apple discussion forums with same issue, so in the end following the instructions in this blog post and voila, Wi-Fi back.

http://blog.hep-cat.de/?p=4760#Mac

As almost everyone has stated on this thread, it's been a problem since before 10.5.8 and that the AC or battery has had no effect.
Some, including me, are still running 10.5.7.:eek:
 
As almost everyone has stated on this thread, it's been a problem since before 10.5.8 and that the AC or battery has had no effect.
Some, including me, are still running 10.5.7.:eek:

as am i, but the problem started when i was running 10.5.5 (about 2 weeks ago), it seems to just have "appeared" out of nowhere -- it has to be something bigger then just OSX.
 
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