M1522NF hangs up

[groovy]

Hi all from Italy.
Here in my lab i have two HP M1522nf with the same, strange issue.
Sometimes they turns off without touching the main power switch, that remains on.
So i turn off and on again and the printer is up again.
Sometimes they hangs up and they stops to respond to front panel inputs.
I think there are a formatter problem with those printers.
There is a way to solve it?
I tried to perform a successful firmware update and a NVRAM initialize, but the problem remain.
Any ideas?
Luigi - digitalix

[cs_steve]

There are formatter issues with that printer.

If you want to repair the printer you would need to replace the formatter; but those are not very good models so you might consider switching to a better model rather than repairing these machines.