iPhone 3GS won't charge from usb power adapter

So I've tried every combo of plugging my phone, USB cord, cube, and wall socket and every one of them works. This is the way it should be. If someone has to go through an intricate order of connecting the phone, cube and cord then I still maintain something must be wrong with the cube. (I posted earlier about replacing two cubes at an apple retail store.)

I keep a USB cord attached to the computer that I use to charge my iPod. When I plug my iPhone into it there seems to be about a 30% chance that iTunes will see my iPhone. If I plug the iPhone into the wall using the power adapter, I get about an 80% success rate. It's really strange. Unplugging and re-plugging in different order helps sometimes but not usually.

my 2 cents.

I received my first ever about 3 weeks ago, and, so far, I'm quite happy. At least I was until this morning.

I wasn't able to charge my phone during the day yesterday and, by late evening, has completely lost its charge and wouldn't turn on. I plugged my iPhone in as soon as I got to my car. By the time I got home (only about 15 minutes later), my phone showed a full charge. I got home and plugged the iPhone into the wall charger and went to bed.

When I got up this morning, my phone showed the battery icon with almost no charge; just a small strip of red at the very end of the icon.

I unplugged it and plugged it back in. Nothing. I tried a different USB cable. Nothing. I plugged it into my car charger. Nothing. I plugged it into 3 different computers (an iMac, and eMac and a PC). Nothing. I tried rebooting the computers with the phone connected. Nothing. I tried rebooting the iPhone while connected to the computers. Nothing.

I'm a huge Apple/Mac supporter and am very frustrated at this development. I do not have any access to my phone or any of the information in it. Any other suggestions?

Sounds like it might be time to get your phone replaced.

BTW my power cube won't charge my 3gs, but it will charge my friend's 3g and 2g. I tried it with another 3gs and it won't charge that one either. Must be something different about how the 3gs charges. I will get this cube replaced.

Had the same problem w my 3GS and was within 30 day window and returned it and my replacement 3GS works perfectly...I think its a problem with the phone itself...I had tried 2-3 cube plugs and they worked only sporadically