Spinning ball every 10sec when using FCP

I have been fighting with constant spinning wheels even on very light projects with only a couple of video 4K files imported. The spinning wheels happen on pretty much every action (even if I click on a clip for example) and they occur every 7-10sec.
Running FCP 10.6.4 and MacOS 12.6.6 on a Macbook Pro M1 Max.

The performance otherwise is lightening fast but I managed to narrow down the conditions when the slow downs and spinning wheels begin to happen.

It's always when I have an external monitor connected.
If I disconnect the external monitor (BenQ PD3220U), the issue goes away.

To make things even more complicated, it seems that if I leave FCP be for a while, the issue resolves itself on its own even with the monitor connected.

I've seen this reported several times but with no real solution. Can anyone offer any insight of what's going on here?

Many thanks!

Hi Domscillator
I use two Benq displays: PD2725U and SW271 that is periodically calibrated. Both monitors work flawless on M1 MacStudio. PD is connected directly by Thunderbolt 3 to the Mac and SW daisy chain connected by USB-C to PD. Benq PD monitors are reputed to be very compatible on Mac. What may be happening with your monitor?. I'd try to update to MacOS 13. I'd also check the connections, if your PD is connected by Th3 try changing the cables and also the connection points on both the Mac and the monitor. Finally, I would look to see how it works through a HDMI connection.

Thank you so much  Buhardilla !

Even though I am on a Macbook Pro (and this could be a differentiator on its own), I did a lot of troubleshooting and realized that the issue is not due to the monitor but it happens when I have my BlackMagic Multidock 10G connected on my Macbook. 

This is just a simple SSD hub and it shouldn't affect the performance at all as I don't use any of the SSDs for Final Cut Pro.

Does this ring a bell at all?

many thanks!