I am a Samsung tech who is having this same problem, me & my other certified techs have all been to site at different times to push reset button on svmi-e at diffeerent times , sometimes we even have to reboot system. I started wwith an older version compact, replaced software up to newest release, and installed an svmi4 that I still had new on shelf, problems started with voice mail locked up , when you would hit vmmsg it would show ringinging 500, so I thought maybe there was a problem with svmi-4 so I replaced at my expense with a svmi-4e, re-set up & still was recieving calls that it was locked up , a couple to 3 times a week. Insisted that customer got a battery backup,they did & still having problems, yesterday took a device caLLED a Kill-awat buy & checked outlets out of ups & outlet both between 119-121v. So I replaced power supply in compact, remembered on the 50si they told us if it was an older one to replace power supply, will keep you updated...
