i don't plug it in the outlet 24/7, i plug it in for probably about 2-3 hours/day. now it just stopped working already, probably after a year!
at first, i thought that the machine is bad. but i used another adapter, it was ok.
after i plug it in, the light will be on for probably less than 20 mins or less, then the adapter will stop working, there is no electricity going thru it, because it feels cold.