Downgrading Mac OS

[kimbo1996]

Hello and thanks! In desperate need of some advice..

I recently purchased an excellent condition refurbished 15' Mid 2015 MBP, 16GB RAM w/ 512GB SSD. It has come with Big Sur 11.1 installed freshly onto it, but unfortunately, some of my audio drivers (namely, some Akai drivers which have been hugely ignored for years by their annoyingly negligent company) aren't yet compatible with Big Sur.

After purchasing the device I reverted it back to it's original OS (El Capitan) and then moved up to Sierra. After this, I started experiencing graphical issues (lines on screen, flickering display, occasional blackouts). I then upgraded BACK to Big Sur in the hope that it may remedy the issues, but they remained the same...

I informed the company which I bought the Macbook from, and they replaced it instantly.

However, the new device has arrived once more with Big Sur, so what I'm needing to know is, did I cause the graphic issues on the original device by downgrading OS? Or, was it faulty from the start... And would creating a USB installer drive and downgrading OS that way be a safer method?

If you got this far into reading, bless you. Any help/advice given to this fledgling music producer would be appreciated.

 

[TonyAguila]

Hello and thanks! In desperate need of some advice..

I recently purchased an excellent condition refurbished 15' Mid 2015 MBP, 16GB RAM w/ 512GB SSD. It has come with Big Sur 11.1 installed freshly onto it, but unfortunately, some of my audio drivers (namely, some Akai drivers which have been hugely ignored for years by their annoyingly negligent company) aren't yet compatible with Big Sur.

After purchasing the device I reverted it back to it's original OS (El Capitan) and then moved up to Sierra. After this, I started experiencing graphical issues (lines on screen, flickering display, occasional blackouts). I then upgraded BACK to Big Sur in the hope that it may remedy the issues, but they remained the same...

I informed the company which I bought the Macbook from, and they replaced it instantly.

However, the new device has arrived once more with Big Sur, so what I'm needing to know is, did I cause the graphic issues on the original device by downgrading OS? Or, was it faulty from the start... And would creating a USB installer drive and downgrading OS that way be a safer method?

If you got this far into reading, bless you. Any help/advice given to this fledgling music producer would be appreciated.

I doubt that the downgrade caused the problem, but I suggest that, if you can get your hands on a USB external drive, it doesn’t have to be SSD, and install Sierra on it, you should be able to test its performance. You may even want to hold onto that external and just run the older OS from it and continue working with Big Sur on the internal drive.

External SSDs have become more affordable lately, so you should get decent performance running your “alternate” system.

 

[kimbo1996]

I doubt that the downgrade caused the problem, but I suggest that, if you can get your hands on a USB external drive, it doesn’t have to be SSD, and install Sierra on it, you should be able to test its performance. You may even want to hold onto that external and just run the older OS from it and continue working with Big Sur on the internal drive.

External SSDs have become more affordable lately, so you should get decent performance running your “alternate” system.

Great! Thanks so much for this suggestion, I have a USB external drive that I can try this with. Much appreciated.