Never had any freezing issues with any prior version of macOS until this Sierra update. Using a Mid 2012 MBP w/ Attached external monitors and Logitech trackball mouse USB attached. About 2 times a day the mouse pointer will beachball and the entire system is frozen until a hard reboot. Will repeat after ~4-6 hrs of usage. Have clean installed with no extra software other than XCode and Logitech LCC mouse software. Have rolled back to clean install via TimeMachine to see if the Logitech software is the issue. Anyone else experiencing daily freezes?