I've got a 2006-2007 vintage 1200x900 G.Weike machine, and since I bought it, I've been replacing the parts of dubious provenance with parts of better quality. I think the next one is going to be the laser PSU, because it appears to be failing.
I bought it last year, and replaced the (factory!) tube immediately, since it was way down on output. I've been having good luck with the machine until this evening, when I started a job on 1/2" acrylic. Normally I can get it to cut in 3 passes at 80%, 6mm/s. Tonight, I wasn't able to get through it at all.
Double-checked mirrors and optics for alignment, and found no issues. Tube plasma is pink and healthy to my eye.
DSP shows correct power numbers, so I don't think it's weird software ballyhoo between the computer and the machine.
Checked the ammeter, and found it's reading a steady 8mA at 80% power. Normally I would see ~16mA there.
The laser PSU is still the factory unit from 2006-2007, and I suspect I'm seeing its swan song. The machine has maybe 40-60 hours of run time on it since the tube was replaced, and a large part of that has been rastering.
What gets me is that it hasn't gone out entirely, and doesn't appear to be fluctuating in output current. It's holding rock steady at 8mA, which is why I'm doing a sanity check to make sure I'm not missing something silly.
Cheers!