Hi, thanks for your reply. It happens every flight around europe, usually during cruise phase with various liners. By the way, my pc specs are: i7-4770, gtx 970, 8gb ram, 2 mechanic hard drive (not ssd). I've also installed "HD sceney mesh V4". Maybe that's the problem? Or not enough RAM so that x-plane is using swap/pagefile on c:\ drive? What you think? Should I double the RAM amount?