Weird USB problem after logicboard replacement.
I have a MBP from a customer which had the logicboard exchanged recently (NVIDIA issue). Customer complains that the USB ports are not working properly, e.g. Time Machine backups failing and the internal keyboard stops working from time to time. On test I could confirm this - backup runs really slow and quitting after 200megs or so. She brought a brand new WD Elements 1TB external harddrive with own power supply which showed the exact same behaviour.
Now it's getting strange - i hook my own backup drive to the machine and backup worked like a charme, so the USB ports of the MBP should be OK. When i hook her WD drive to my 2009 iMac it's working fine too. So the WD is obviously alright.
WTF is going on here? Any idea?
Ist dies eine gute Frage?