I have an Xtool D1 Pro with the 40w upgrade.
I have only had it for a few weeks, and use it sporadically to cut out small parts for craft projects.
I fired it up today and was dismayed when I got this:
The leftmost image was 45% power, that I had been using for cutting 5/32 plywood.
I triple checked the focus, I tried reducing the power, which did result in a finer kerf, but there was no way I would be using this at such low power when I paid what I did for the 40 watts.
So, before I started a support ticket, I decied to check all the stuff I figured they would want me to do.
The kit came with a couple of extra lenses, which was pretty easy to replace, and it turned out that was my problem. Dirty, I guess. I will see how the old lens responds to some cleaning effort.
Cut at 50% power.
I used a 20w machine for over a year and never experienced this, so it must be a matter of air flow around the lens, allowing for more contamination.
Hope this helps someone else.