LLE audio suddenly needs realtime CPU priority (?!)

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I'm on build 5.0-12017 on Windows 10, and all of a sudden, LLE Recompiler is causing Dolphin to chug down to unplayable speeds unless I use Task Manager to force Dolphin's CPU priority to Realtime (High priority doesn't work), which according to Raymond Chen, is an absolutely terrible idea. Any ideas as to what is going on?