Logic Pro X 10.8 System Overload

I updated Logic Pro X from version 10.7.9 (which was great) to the new version 10.8.

Now I can't work due to repeated System Overload messages every minute.

This happens in projects that did not cause any problems when opened with the old version of Logic.

I also tried to downgrade but now even the previous version gives me Overload problems.

I tried resetting everything, throwing away the preferences, I did a full audio reset of all the plug-ins, tried to increase the I/O buffer size, the multithreading options, nothing helped to solve the problem.

Where is all the power that Apple promised me when I spent more than 5k USD on my new 16" MacBook Pro M1?

Now I feel like I have an Intel i5!!!

Some more details about my issue:

Macbook Pro M1 Pro 16", 32G RAM, 4TB SSD

MacOS Sonoma 14.1.1

Logic Pro X 10.8

Instruments who could cause the issue:

Serum 1.3.6.8

Sylenth 3.0.73

Spire 1.5.16

Kontakt 7.6.1

My project has 14 instrument tracks (which never all play at the same time) out of a total of 38 tracks.

With the old Logic I could also open more than 30 instruments without having any Overload.

When the song is playing the processing meter does not indicate any risk of overload and the processing threads are around 25%, suddenly a CPU peak occurs and the system goes into Overload.

Downgrading back to the Logic version 10.7.9 (who was working great before the update) is now also affected by System Overload issues.

Any advice?