I have several MS425's in production and not experienced anything like that.  I have; however, experienced where one particular one seems to go offline briefly and randomly after we had big power outage on that side of town.  I had thought it to be a power issue with the switch, or potentially a power supply...but after verifying I have good power and swapping power supplies I have wondered if it were something to do with a Cisco switch in this network and PVST (see other thread about all this).   Never did I have to do a hard reboot though, so doesn't sound like this is your issue. ... View more