I just got an 15" MBP and occasionally it will freeze while booting. The will get to the gray apple screen and the wheel will stop spinning. It also sometimes has issues coming out of sleep. I went to the Apple Store and they ran a drive repair and we booted it multiple times with no issue. My first boot after I brought it home and the issue returned. I am new to Mac's and am not sure where to look next. If I take it in for hardware repair they said it could be 7-10 days. Any ideas? Thanks in advance.