Not nearly enough info for anyone to do anything but make blind guesses.

Stop calling them hards. Use HDD for Hard Disk Drive or SSD for Solid State Drive so that everyone is speaking the same language.

List your MacOS and version, whether your MBP has an HDD, SSD or Fusion and the size. Does your MBP have a Retina screen or no — yes, it makes a difference.

How are you hooking up your BIAB drive and what version of BIAB do you have?

Are you using and disk utilities? If so, stop — they don't do any good but it's helpful to know.

I am an experienced Mac tech.


BIAB 2024 Audiophile Mac
24Core/60CoreGPU M2 MacStudioUltra/8TB/192GB Sequoia, M1 MBAir, 2012 MBP
Digital Performer11, LogicPro, Finale27/Dorico/Encore/SmartScorePro64/Notion6 /Overture5