Timer on some program on my laptop cuts off allcalls in 6.5 mins

I am hoping someone can have an idea on what's going on. For the last 10 days or so I have an issue. I work over the phone with a Magic Jack Go, have never had this issue till now. Every incoming call cuts off and drops at 6.5 minutes. All internet cables and even modem were swapped out, troubleshooted w internt provider and then days with Magic Jack. Turns out it is some app or program that is doing this, and I have tried to find it to no avail. Have de-activated firewall, antivirus, windows defender, ultrasurf VPN, unistalled driver booster, driver updater from iobit and no change. Urgent as I have been unable to work, cannot have dropped calls as am phone interpreter. I am in deep trouble. Can anyone please help or suggest?