Select Diagnostic Startup. OK and Reboot.
Run Latency Mon again. Does it still say
"Your system appears to be having trouble handling real-time audio and other tasks..."
If so go back into msconfig and check Normal Startup, OK and reboot.
If it now seems happy with your system then go into msconfig and under Services, check Hide Microsoft Service then uncheck all that remain. OK and reboot. What does Latency mon say now? If that helps then go back into msconfig and check 1/2 of the services, OK and reboot. Try to isolate it down to a particular service. It could also be a Startup item. These are now controlled by Task Manager but in msconfig if you go to Startup you will have a link to the Task Manager where you can try turning off all Startup items.