I have had this router for a few years, and it has always been a PITA to use because the lever that clamps the height adjustment in place pops open during use. I have tried several times to tighten, then loosen the adjustment nut on the lever, to no avail. I had pretty much developed the habit of holding the end of the lever with my fingertips while routing. But today, I just got tired of that, and decided to either fix it or make it worse. If I couldn't fix it, I was prepared to buy a new one.
I had never before really examined the lever with the idea of trying to find the flaw in the design, but the flaw was easy to see. The portion of the lever that presses on the flat washer, that in turn presses on the housing, to pull it tight around the motor, was too thick to allow the lever to go over center, which would hold it in place.
A slight adjustment with a file and the lever now snaps into place and stays there.
This is the router:
And the latch on the back side:
I didn't take a pic of the lever before I filed it, but you can see from the depth of the notch how much metal I removed:
And assembled back together:
I have no idea how popular this router is, so I may not help many people with this info. But this may apply to other brands as well.
So, I repaired my way out of getting a new router.