While watching the performance meter I discovered if you DO NOT hit stop when replaying a log (use only the pause button) The CPU usage will drop back to almost nothing when paused.
If you hit STOP, the CPU gets tied up with "User Time" and will not restore free processor time until SP is shut down. Repeated several times to confirm it.
When "playing"
Processor 100%
Priveledged time 87%
User Time = 14-18%
When "paused"
Processor 1-2%
Priveledged time 1-2%
User Time = 0-1%
When "stopped"
Processor 100%
Priveledged time 1%
User Time = 99%
Anyway, might help you narrow down that issue.
Found Something on CPU time
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