Hey. I hope this is the right section.

I bought a second "red and black" 130w co2 laser. First one is running fine, all good.

The second one - At some times I hear electric cracking noise, discharge somewhere near tube.

The first machine does perfectly engrave at 150mm/s and 9% power (mat finish, perfect).

The second machine even on 500mm/s and 9% power does engrave at least 0.5mm deep.

Both machines are supposed to be identical..

Any suggestions appreciated. Thank you in advance.