Black frames in nested clips, footage colour & exposure is being changed, poor performance (24.5)

so i am a real estate videographer and i edit 5 days a week on a mac mini 2023 16g ram, 256 internal storage.

i cave well over 3 quarters of my storage free as i back up my clips to ssd.

over the past week i have been trying desperately to edit videos but have been experiencing multiple bugs that are causing headaches in the process, such as nested clips blacking out frames, imported footages colour & exposure is being changed (well exposed clip will lose all detail, become over saturated and grainy) i re imported footage and it fixed this for about an hour before it reverted to the afformentioned state.

playback is nearly impossible without rendering even at 1/8th quality and stabilizing clips is taking an absurd amount of time (2 second clip will take 15 minutes)

i have cleared my system cache and tried reverting my premier to an older version to no avail.

is anyone else experiencing this and how can i get my system running normally again?

thanks!

Mod note: The title of your post was changed to reflect your issues and for search.