My screen moves from side-to-side for no apparent reason
Hi - I am being plagued by this problem where my screen will freeze, move from side-to-side and I have no control over it until it stops. Does anyone know why this is happening and what I can do to stop it? I have had the problem before but did not save the answer. Help!
I am running a new iMac, with up to date Yosemite and I have a second monitor - Cinema Display.
iMac, MBP, Mini, Mac OS X (10.6.3)