since upgrading to 1.8 ( 490 0r so fixes) when i start up xplane 12 and load the challenger cpu goes to 100 percent for about 30 seconds then back down to 65 percent. this happens again about 5 minutes later and then the rest of the flight goes well (45 minutes) till on turning onto final, cpu 100 percent for 20 seconds and then back to normal. went back to v1.7 and problem went away. any ideas??