After starting the program, go to Help > Utilities > Display Log text file of Yellow/Green messages.

At the top of the file will be your startup details (reads from latest to earliest), like this:

Bootup was optimal, set to fast [2021.814.0, 4/01/2021 4:41:41 AM]
Bootup time in milliseconds =8,057 [2021.814.0, 4/01/2021 4:41:41 AM]
Time to scan unknown VST plugins = 6 ms [2021.814.0, 4/01/2021 4:41:40 AM]
Time to scan known VST plugins = 27 ms [2021.814.0, 4/01/2021 4:41:40 AM]
Time to scan AU plugins = 0 ms [2021.814.0, 4/01/2021 4:41:40 AM]
Time to scan ALL plugins = 33 ms [2021.814.0, 4/01/2021 4:41:40 AM]
Time to Count Plugins in ms =419. Plugins counted=58 [2021.814.0, 4/01/2021 4:41:40 AM]
Scanning for plugins... [2021.814.0, 4/01/2021 4:41:39 AM]
**** New Session started at : 4/01/2021 4:41:39 AM


That might give you a clue to what is possibly taking up the time.


BIAB & RB2025 Win.(Audiophile), Sonar Platinum, Cakewalk by Bandlab, Izotope Prod.Bundle, Roland RD-1000, Synthogy Ivory, Kontakt, Focusrite 18i20, KetronSD2, NS40M Monitors, Pioneer Active Monitors, AKG K271 Studio H'phones