Umm, I don't think thats possible. Looks like theres something wrong with your iPhone battery. Battery shouldn't be losing more charge than it's gaining while plugged in....unless you got the speakers on high and are listening to music.
Edit: Are you charging an iPhone?
Charging an Android phone. It charges on my old 2008 Dell laptop as well as through the wall outlet. But my guess is that the new RMBP puts out very slightly less power than my old laptop did.
(In other words:
With old laptop it charges slowly
With RMBP it loses energy slowly
With no charging it loses energy at the normal rate
And wall outlet it charges quickly.)
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If you're doing something very intensive with your phone (playing a graphics-heavy game, for instance) I wouldn't be surprised if the phone is using more power than it's gaining while charging. Is that the case, or is it somehow losing charge while it's plugged in and not being used? In any case, trying to increase the output of your USB port sounds like a good way to damage your computer...and your phone.
Yeah, that's what's happening. I'm using my phone as a Wifi hotspot. But even without using it as a hotspot, it charges very slowly (hence why I was wondering if I could increase the power output).
Sammich, here's what I got from the system profile:
LG Android USB Device:
Product ID: 0x61a6
Vendor ID: 0x1004 (LG Electronics Inc.)
Version: 1.00
Serial Number: A00000288D002F
Speed: Up to 480 Mb/sec
Manufacturer: LG Electronics Inc.
Location ID: 0x1d110000 / 7
Current Available (mA): 500
Current Required (mA): 400