iPhone connects and disconnects for no reason.
My iPhone 4 and iPhone 5s won't stay connected to my new (Jan. 2015) Macbook Pro Retina 13". It will continuously connect and disconnect from the computer (not physically). What can/should I do? Is this a hard drive/motherboard issue? I have tried multiple chords and phones and the only one that stayed connected was my iPhone 3.
MacBook Pro (Retina, 13-inch, Mid 2014), OS X Yosemite (10.10.2)