fsx:se doesn't respond to keyboard and sound gone randomly

so recently like 1 week ago, i installed pmdg 747 v3 and 777 and some other payware addons, and saturday last week i was doing some extended range flight, but i got some trouble suddenly when i was flying using the 747-400 i wanna control the plane manually for a while to line up with the route, but suddenly the fsx become unresponsive to key command, no key was working, i already checked if the numlock is not active. after that problem encounter, i decide to restart my flight and same thing happened after restart flight, restart fsx, and after restarting the pc, but after i restarted the pc and launch the fsx again, the same problem happened when i was setting up the airplane before fly and even worse, sound also gone, and both problem still goin on till now. i already do some research how to fix this 2 problems but still cant find any solution for the problems, can someone please help me with this problems? thank you