BSOD: 0x00000109 at 12:33:00 am every third day

I just started getting this crash, three times, twice at almost exactly the same time. I scanned the disk and ran SFC. SFC kicks up a lot of errors but I believe it is due to directories being redirected to a D: drive and they are not new issues and SFC "ignores" them. This is Windows 8 64 bit but I assume it's not significant.

Error 7/8/2013 12:33:53 AM BugCheck 1001 None

The computer has rebooted from a bugcheck. The bugcheck was: 0x00000109 (0xa3a039d8b3bd5987, 0xb3b7465f063a5963, 0xfffff8010dd55710, 0x0000000000000001). A dump was saved in: C:\Windows\MEMORY.DMP. Report Id: 070813-13057-01.

I notice that at the time, or just before, of the error a task starts from the scheduler:

Actions : %SystemRoot%\ehome\ehPrivJob.exe /DoRecoveryTasks $(Arg0)
Path : \Microsoft\Windows\Media Center\DispatchRecoveryTasks
Name : DispatchRecoveryTasks
LastRunTime : 7/8/2013 12:33:52 AM

I am also getting another occasional BSOD:

Error 7/5/2013 9:11:26 PM BugCheck 1001 None

The computer has rebooted from a bugcheck. The bugcheck was: 0x0000001a (0x0000000000041284, 0x0000000059bc8001, 0x000000000003ae2d, 0xfffff70001080000). A dump was saved in: C:\Windows\MEMORY.DMP. Report Id: 070513-23727-01.

I couldn't find any software that has been recently changed or drivers that were updated although there have been routine automatic Windows Updates.