Orthogonally to the suggestions from Pawel, I'd suggest also trying to analyse what the step is actually doing while it's "being slow", with ProcessMonitor. Even the built in Windows 10 Resource Monitor, which you can get to from the Task Manager in Windows, can be fairly useful as it allows you to isolate and drill into individual processes to monitor their behaviour as well, including handles/files opened/loaded etc etc. Understanding what it's actually doing and working out why this step is being slow might give you ideas on how to avoid it.