I'm beginning to wonder about the scheduled task thing again. Around 12:30 PST SI started to operate at nominal speeds. Now pretty speedy.
I got a theory that your code has a loop that manages scheduled tasks. If this loop gets out of sync with actual time for some reason it might reschedule tasks in a different way and run something during the market hours that really burdens the CPU. If this is what is happening, the current task that is causing the slowness is a medium grade burden, not the killer that hit you a few months ago.
If you can look through the scheduled task stuff in the code you might be able to find something. Wish I knew what to look for, but it is something that designates time of day to launch and this launcher is cutting loose from correct time somehow.
Just a WAG from far away, but SOMETHING is going on, that is certain.