Logic 10.5 scans all audio units before opening.

logic 10.5 now scans all 267 audio units every time on opening. Takes 2 minutes.

Do you have Waves plugins? If so, there have been reports about some of them causing that issue.

Alternately, IIRW, if you are using Automap from Novation, there is an option in their app to enable to prevent same...

 

Also, here is what I gleaned from other sites:

-LUG:

• It was usually either a permissions issue related to the AudioUnits cache or some old Waves waveshells not scanning correctly, so Logic gets stuck in a loop rescannning them on every launch. I would check the caches folder:
  
  • ~/Library/Caches/AudioUnitCache

There should be a decently sized com.apple.audiounits.cache file in there. If there isn't or it's 0kb, then maybe something is preventing it from being written. Try deleting the whole AudioUnitCache folder and let Logic recreate it. Maybe that will fix it. Also check ~/Library/Audio/Plug-Ins/Components to see if there are multiple waveshells present, which can sometimes clash with each other. Over the years I've had to run the Waves AU reg utility to fix issues with their plugins. It used to be found in the Applications/Waves/Waveshells folder.

 

OR

 

• 1.Copy All files from Macintosh HD /Library/Audio/Plug-Ins/Components/
  2.Paste to Macintosh HD/Users/your user name/Library/Audio/Plug-Ins/Components/
  3.Click on Replace All
  Next time when you start logic it will scan all audio units only once and the scan wont reoccur in every subsequent startup.

 

MacProVideo:

• Make sure they are under Hard Drive > Library > Audio > Plug-ins > Components and not in your user Library.
  I also suggest you delete your Audio Unit cache under
  User account > Library > Cache

Thanks yes I'm pretty sure its the Waveshells causing it as it was cited reason for Logic crashing a couple of times. I'll follow your suggestions. Thanks again.