FVS336G v1 Random Reboots

I believe this unit has the built in power supply correct? Its been a while since I had the v1. If it has a external power supply, you could try a new one. random reboots are usually a sign of a dieing power source. Is it on a battery backup? If so, try taking it off it to see if it corrects the issue. If it does, then the UPS is most likely causing the issues and needs to be replaced. The failing VPN may be an indication that the config needs to be wiped and reprogrammed in. To see if the firmware is corrupt, you can always make a backup of your config, reload the firmware and I suggest manually re-programming in your config. If the config is corrupt and you reload it back in, then you're loading the same problem in again.