Mac mini main display background looks odd at random times

Main dispay background looks odd at random times.

I've attached a screenshot and I'm hoping someone knows what it is or what causes it.

Note: My mac mini works fine otherwise, just the desktop background on my main monitor (I have 2 screens) looks like this.

System info:

 Model Name: Mac mini

 Model Identifier: Mac14,3

 Model Number: Z16L000JYLL/A

 Chip: Apple M2

 Total Number of Cores: 8 (4 performance and 4 efficiency)

 Memory: 16 GB

macOS version: Tahoe 26.1