I'm having problems with calls dropping after 3 minutes. I'm using 3810's connected to 8510's and have the voice setup on SVC. I was running Frame-Relay and didn't have problems with voice till I moved to ATM. Has anyone else had problems with SVC's. I thought it could be the clocking since I'm getting it from the 8510 instead of the Telco, but network clocking isn't my strong point.